diff --git a/.github/copilot-instructions.md b/.github/copilot-instructions.md
index d0bcb14..0ad4e93 100644
--- a/.github/copilot-instructions.md
+++ b/.github/copilot-instructions.md
@@ -1,85 +1,83 @@
-Purpose
--------
-This file gives concise, actionable guidance for AI coding agents working on the `webinfo` Go module.
-
-What this project does
-----------------------
-Extracts metadata (title, description, canonical, image, etc.) from web pages and provides utilities
-to fetch and save representative images and create thumbnails.
-
-Quick entry points
-------------------
-- **Primary package**: `webinfo` — key files:
-  - `fetch.go` (core `Fetch` function and encoding handling)
-  - `webinfo.go` (`Webinfo` type, `DownloadImage`, and `DownloadThumbnail`)
-  - `errs.go` (error sentinel values)
-  - `fetch_test.go` (behavioral tests and examples)
-- **Go module**: `go 1.25` (see `go.mod`).
-
-Developer workflows
--------------------
-- Run full CI/test workflow using the Taskfile (recommended if `task` is installed):
-  - `task test` — runs `go mod verify`, `go test -shuffle on ./...`, `govulncheck`, and `golangci-lint-v2` as configured in `Taskfile.yml`.
-- Quick test: `go test ./...` (useful during fast iteration).
-- Prepare module: `go mod tidy -v -go=1.25` (mirrors `prepare` in `Taskfile.yml`).
-
-Project-specific conventions and patterns
-----------------------------------------
-- Error handling: uses `github.com/goark/errs`. Prefer `errs.Wrap(err, errs.WithContext("key", val))` for context-rich errors and `errs.Join` when combining close errors in `defer`.
-- HTTP fetching: uses `github.com/goark/fetch`. Typical pattern:
-  - Parse URL with `fetch.URL(...)`.
-  - Use `fetch.New(...).GetWithContext(ctx, parsed, fetch.WithRequestHeaderSet("User-Agent", ua))`.
-- Default User-Agent: `getUserAgent("")` returns a dummy UA string. Functions accept a `userAgent` param but fall back to this default.
-- Encoding: `Fetch` peeks the first 1024 bytes and uses `charset.DetermineEncoding` and `encoding.GetEncoding(name)` to decode response bodies before HTML parsing — preserve this approach when touching parsing logic.
-- HTML parsing: `goquery` is used to select head elements and meta tags. Extraction precedence is explicit in `fetch.go` (title → `twitter:title`/`og:title`, description → `twitter:description`/`og:description`, image → `twitter:image`/`og:image`). Follow this precedence in code changes or tests.
-
-Image download and thumbnail notes
----------------------------------
-- `DownloadImage` (in `webinfo.go`) downloads `w.ImageURL` and saves it to disk. It determines the output file extension using this order:
-  1) extension from the URL path,
-  2) extensions inferred from the response `Content-Type` header,
-  3) sniffing the first up to 512 bytes via `http.DetectContentType`,
-  4) fallback to `.img` if none found.
-  When sniffing, the read bytes are prepended back into the response body with `io.MultiReader` so the full image is written.
-- `DownloadThumbnail` (added to `webinfo.go`) downloads the original image (via `DownloadImage`), resizes it to a requested width (preserving aspect ratio) and writes a thumbnail. Implementation notes:
-  - The code currently uses a local nearest-neighbor scaler (no external `x/image/draw` dependency) to avoid adding module requirements.
-  - The method accepts `width` (default 150 when <= 0), `destDir`, and `temporary` flags. When `destDir` is empty the method forces creation of a temporary file.
-  - When `temporary` is false, the thumbnail filename is derived from the original image basename with `-thumb` appended before the extension.
-
-I/O and cleanup
-----------------
-- Response bodies and files are closed; close errors are wrapped/joined with any existing error.
-- Errors encountered while parsing the URL, fetching, reading, sniffing, creating directories/files, or copying data are wrapped with contextual information (e.g. `"url"`, `"path"`, `"dir"`, `"file"`) using the `errs` package.
-
-Tests and examples
-------------------
-- Tests use `net/http/httptest` for deterministic responses (encoding tests use `golang.org/x/text/encoding/japanese`). Inspect `fetch_test.go` for examples of:
-  - Redirect handling and validation of `Location`.
-  - Encoding tests for Shift_JIS and ISO-2022-JP.
-  - Verifying `User-Agent` header usage.
-- Example usage patterns to follow when adding code or tests:
-  - Fetch: `info, err := Fetch(ctx, "https://example.com", "")` — empty UA uses the default.
-  - Download image: `outPath, err := w.DownloadImage(ctx, "images", true)`
-  - Download thumbnail: `thumbPath, err := w.DownloadThumbnail(ctx, "thumbnails", 150, false)`
-
-External dependencies & integration points
-----------------------------------------
-- Key dependencies in `go.mod`: `github.com/goark/fetch`, `github.com/goark/errs`, `github.com/PuerkitoBio/goquery`, `golang.org/x/text` (encodings).
-- The repository intentionally avoids adding `golang.org/x/image/draw` as a dependency; if you need higher-quality scaling consider adding it and updating `go.mod` and tests.
-- The `Taskfile.yml` runs additional tools: `govulncheck`, `golangci-lint-v2`, and (optionally) `nancy` via `depm` — keep CI tool invocations in sync when adding dependencies.
-
-When modifying public APIs
--------------------------
-- Maintain existing error-wrapping conventions (`errs.Wrap`, `errs.WithContext`).
-- Preserve encoding detection behavior and the 1024-byte peek in `Fetch` unless a clear, tested performance reason exists.
-- Preserve `DownloadImage`'s extension-detection order and the behavior of `temporary` vs permanent files. When adding `DownloadThumbnail` behavior or changing file-naming semantics, update tests accordingly.
-
-Where to look next (high-value files)
--------------------------------------
-- `fetch.go` — how pages are fetched, decoded and parsed.
-- `webinfo.go` — `Webinfo` type, `DownloadImage`, and `DownloadThumbnail` implementations.
-- `fetch_test.go` — canonical tests and examples you should mirror for new behaviors.
-- `errs.go` and `go.mod` — error constants and dependency hints.
-- `Taskfile.yml` — canonical developer/test/lint workflow.
-
-If anything above is unclear or you want small patches, test templates, or a CI-safe refactor suggestion, tell me which area to expand and I will iterate.
+# Copilot Instructions for `goark/webinfo`
+
+## Project purpose
+
+`webinfo` extracts metadata from web pages and provides helpers for
+image download and thumbnail generation.
+
+## Design principles
+
+- Keep public APIs small and explicit.
+- Preserve metadata extraction precedence and deterministic behavior.
+- Keep context-based fetch operations as the default path.
+- Preserve compatibility of exported symbols when possible.
+
+## Error handling
+
+- Use `github.com/goark/errs` for internal error handling.
+- Prefer `errs.Wrap`, `errs.Join`, and `errs.WithContext`.
+- Keep `errors.Is` compatibility for callers.
+- Keep sentinel errors stable (`ErrInvalidURL`, `ErrNoImageURL`, `ErrNullPointer`).
+- Include useful context keys such as `url`, `path`, and `dir`.
+
+## Fetch and parsing behavior
+
+- Use `github.com/goark/fetch` for HTTP operations.
+- Keep the default User-Agent fallback behavior.
+- Preserve encoding detection flow in `Fetch` (1024-byte peek + charset detection).
+- Keep extraction precedence unchanged:
+  - title: `title` -> `twitter:title` -> `og:title`
+  - description: `meta[name=description]` -> `twitter:description` -> `og:description`
+  - image: `twitter:image` -> `og:image`
+
+## Image and thumbnail behavior
+
+- Keep `DownloadImage` extension detection order:
+  1) URL path extension
+  2) `Content-Type` based extension
+  3) content sniffing (`http.DetectContentType`)
+  4) fallback `.img`
+- Keep the sniffed bytes prepended back to the body reader.
+- Keep temporary/permanent file behavior stable.
+- Keep thumbnail default width behavior (`width <= 0` -> `150`).
+
+## Coding style
+
+- Write idiomatic Go with straightforward control flow.
+- Avoid unnecessary dependencies.
+- Keep comments concise and in English.
+
+## Testing and validation
+
+- Add or update tests for behavior changes.
+- Prefer local validation with Taskfile targets:
+  - `task test`
+  - `task govulncheck`
+
+## Documentation
+
+- Keep `README.md` aligned with public API behavior.
+- Keep examples concise and runnable.
+
+## Release process
+
+- Create release tags from `main`.
+- Use semantic versioning tags in `vMAJOR.MINOR.PATCH` format.
+- Ensure repository is clean and synced before tagging.
+
+Release steps:
+
+1. Ensure `main` is up to date.
+2. Create annotated tag:
+  - `git tag -a vX.Y.Z -m "Release vX.Y.Z"`
+3. Push tag:
+  - `git push origin vX.Y.Z`
+4. Create GitHub release with autogenerated notes:
+  - `gh release create vX.Y.Z --generate-notes`
+
+Verification steps:
+
+- Check tag exists:
+  - `git tag -l "vX.Y.Z"`
+- Check release exists:
+  - `gh release view vX.Y.Z`
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..43e5071
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,44 @@
+name: ci
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  test-and-lint:
+    name: lint and test
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+
+      - uses: actions/setup-go@v6
+        with:
+          go-version-file: go.mod
+          cache-dependency-path: go.sum
+
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v9
+        with:
+          version: latest
+          args: --enable gosec
+
+      - name: Test module
+        run: go test -shuffle on ./...
+
+  govulncheck:
+    name: govulncheck
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Run govulncheck
+        uses: golang/govulncheck-action@v1
+        with:
+          go-version-file: go.mod
+          go-package: ./...
+          repo-checkout: false
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
new file mode 100644
index 0000000..9db6ba2
--- /dev/null
+++ b/.github/workflows/codeql.yml
@@ -0,0 +1,35 @@
+name: CodeQL
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+  schedule:
+    - cron: "0 20 * * 0"
+
+permissions:
+  actions: read
+  contents: read
+  security-events: write
+
+jobs:
+  analyze:
+    name: Analyze
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v6
+
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@v3
+        with:
+          languages: go
+
+      - name: Autobuild
+        uses: github/codeql-action/autobuild@v3
+
+      - name: Perform CodeQL analysis
+        uses: github/codeql-action/analyze@v3
diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
deleted file mode 100644
index b0c9ba2..0000000
--- a/.github/workflows/lint.yml
+++ /dev/null
@@ -1,50 +0,0 @@
-name: lint
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-
-permissions:
-  contents: read
-  # Optional: allow read access to pull request. Use with `only-new-issues` option.
-  # pull-requests: read
-jobs:
-  golangci:
-    name: lint
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v5
-      - uses: actions/setup-go@v6
-        with:
-          go-version-file: 'go.mod'
-      - name: golangci-lint
-        uses: golangci/golangci-lint-action@v9
-        with:
-          # Optional: version of golangci-lint to use in form of v1.2 or v1.2.3 or `latest` to use the latest version
-          version: latest
-
-          # Optional: working directory, useful for monorepos
-          # working-directory: somedir
-
-          # Optional: golangci-lint command line arguments.
-          args: --enable gosec
-
-          # Optional: show only new issues if it's a pull request. The default value is `false`.
-          # only-new-issues: true
-
-          # Optional: if set to true then the all caching functionality will be complete disabled,
-          #           takes precedence over all other caching options.
-          # skip-cache: true
-
-          # Optional: if set to true then the action don't cache or restore ~/go/pkg.
-          # skip-pkg-cache: true
-
-          # Optional: if set to true then the action don't cache or restore ~/.cache/go-build.
-          # skip-build-cache: true
-      - name: testing
-        run: go test -shuffle on ./...
-      - name: install govulncheck
-        run: go install golang.org/x/vuln/cmd/govulncheck@latest
-      - name: running govulncheck
-        run: govulncheck ./...
diff --git a/README.md b/README.md
index 7186c97..739741a 100644
--- a/README.md
+++ b/README.md
@@ -1,179 +1,109 @@
-# [webinfo] -- Extract metadata and structured information from web pages
+# [webinfo] -- Extract metadata from web pages
 
-[![lint status](https://github.com/goark/webinfo/workflows/lint/badge.svg)](https://github.com/goark/webinfo/actions)
-[![GitHub license](https://img.shields.io/badge/license-Apache%202-blue.svg)](https://raw.githubusercontent.com/goark/webinfo/master/LICENSE)
-[![GitHub release](http://img.shields.io/github/release/goark/webinfo.svg)](https://github.com/goark/webinfo/releases/latest)
+[![ci status](https://github.com/goark/webinfo/workflows/ci/badge.svg)](https://github.com/goark/webinfo/actions)
+[![codeql status](https://github.com/goark/webinfo/workflows/CodeQL/badge.svg)](https://github.com/goark/webinfo/actions)
+[![GitHub license](https://img.shields.io/badge/license-Apache%202-blue.svg)](https://raw.githubusercontent.com/goark/webinfo/main/LICENSE)
+[![GitHub release](https://img.shields.io/github/release/goark/webinfo.svg)](https://github.com/goark/webinfo/releases/latest)
 [![Go reference](https://pkg.go.dev/badge/github.com/goark/webinfo.svg)](https://pkg.go.dev/github.com/goark/webinfo)
 
-[`webinfo`][webinfo] is a small Go module that extracts common metadata from web pages and provides utilities
-to download representative images and create thumbnails.
+`webinfo` extracts common metadata (title, description, canonical, image, etc.)
+from web pages and provides helpers to download images and generate thumbnails.
 
-## Quick overview
+## Design goals
 
-- **Package**: `webinfo`
-- **Repository**: `github.com/goark/webinfo`
-- **Purpose**: fetch page metadata (title, description, canonical, image, etc.) and download images
+- Keep metadata extraction simple and deterministic.
+- Use clear precedence rules for HTML/meta parsing.
+- Provide practical image utilities with minimal API surface.
+- Keep context-aware network operations as the default style.
 
-## Features
+## Development
 
-- Fetch page metadata with `Fetch` (handles encodings and meta tag precedence).
-- Download an image referenced by `Webinfo.ImageURL` using `(*Webinfo).DownloadImage`.
-- Create a thumbnail from the referenced image using `(*Webinfo).DownloadThumbnail`.
+### Requirements
 
-## Install
+- Go 1.25.10 or later
+- [Task](https://taskfile.dev/) command (local tool for this repository)
 
-Use Go modules (Go 1.25+ as used by the project):
+### Local validation
 
-```bash
-go get github.com/goark/webinfo@latest
+```text
+task test
+task govulncheck
 ```
 
-## Basic usage
-
-Example showing fetch and download thumbnail (error handling omitted for brevity):
+Run all maintenance tasks:
 
-```go
-package main
-
-import (
-    "context"
-    "fmt"
-
-    "github.com/goark/webinfo"
-)
-
-func main() {
-    ctx := context.Background()
-    // Fetch metadata for a page (empty UA uses default)
-    info, err := webinfo.Fetch(ctx, "https://text.baldanders.info/", "")
-    if err != nil {
-        fmt.Printf("error detail:\n%+v\n", err)
-        return
-    }
-
-    // Download thumbnail: width 150, to directory "thumbnails", permanent file
-    thumbPath, err := info.DownloadThumbnail(ctx, "thumbnails", 150, false)
-    if err != nil {
-        fmt.Printf("error detail:\n%+v\n", err)
-        return
-    }
-    fmt.Println("thumbnail saved:", thumbPath)
-}
+```text
+task
 ```
 
-### API notes
-
-- `Fetch(ctx, url, userAgent)` — Parse and extract metadata. Pass an empty userAgent to use the module default.
-- `(*Webinfo).DownloadImage(ctx, destDir, temporary)` — Download the image in `Webinfo.ImageURL` and save it. If
-  `temporary` is true (or `destDir` is empty), a temporary file is created.
-- `(*Webinfo).DownloadThumbnail(ctx, destDir, width, temporary)` — Download the referenced image and produce a
-  thumbnail resized to `width` pixels (height is preserved by aspect ratio). If `destDir` is empty the method
-  creates a temporary file; when `temporary` is false the thumbnail file is named based on the original image
-  name with `-thumb` appended before the extension.
+## CI Workflows
 
-Note on defaults and test hooks:
+- `ci`: lint (`golangci-lint` with `gosec`), tests, and `govulncheck`
+- `CodeQL`: scheduled and push/PR static analysis
 
-- **Default width**: If `width <= 0` is passed to `DownloadThumbnail`, the method uses a default width of 150 pixels.
-- **Extension detection**: `DownloadImage` determines an output extension from the URL path, the response
-  `Content-Type` (via `mime.ExtensionsByType`), or by sniffing up to the first 512 bytes with `http.DetectContentType`.
-- **Test hooks / injection points**: For easier testing the package exposes a few package-level variables that
-  tests can override:
-  - `createFile`: used to create temporary or permanent files (wraps `os.CreateTemp` / `os.Create`). Override to
-    simulate file-creation failures.
-  - `decodeImage`: wrapper around `image.Decode` used by `DownloadThumbnail` — override to simulate decode results
-    (for example, to return a zero-dimension image).
-  - `outputImage`: encoder that writes the thumbnail image to disk (wraps `jpeg.Encode`, `png.Encode`, etc.).
-    Override to simulate encoder failures.
+## Usage
 
-These hooks are intended for tests and let callers reproduce rare I/O or encoding failures without changing
-production behavior.
+### Install and import
 
-- **HTTP client timeout**: `DownloadImage` uses an HTTP client with a default 30-second `Timeout` for the whole
-  request; tests can override this by replacing the `newHTTPClient` package variable.
-
-## Test examples
-
-Below are short examples showing how to override the package-level hooks from a test to simulate failures.
-These snippets are intended for `*_test.go` files and assume the usual `testing` and `net/http/httptest` helpers.
-
-1) Simulate thumbnail temporary-file creation failure (override `createFile`):
+```bash
+go get github.com/goark/webinfo@latest
+```
 
 ```go
-// in your test function
-orig := createFile
-defer func() { createFile = orig }()
-createFile = func(temp bool, dir, pattern string) (*os.File, error) {
-  // fail only for thumbnail temp pattern
-  if temp && strings.Contains(pattern, "webinfo-thumb-") {
-    return nil, errors.New("simulated thumbnail temp create failure")
-  }
-  return orig(temp, dir, pattern)
-}
-
-// then call the method under test
-_, err := info.DownloadThumbnail(ctx, t.TempDir(), 50, true)
-// assert err != nil
+import "github.com/goark/webinfo"
 ```
 
-2) Simulate a zero-dimension decoded image (override `decodeImage`):
+### Fetch metadata
 
 ```go
-origDecode := decodeImage
-defer func() { decodeImage = origDecode }()
-decodeImage = func(r io.Reader) (image.Image, string, error) {
-  // return an image with zero width to hit the origW==0 error path
-  return image.NewRGBA(image.Rect(0, 0, 0, 10)), "png", nil
+ctx := context.Background()
+info, err := webinfo.Fetch(ctx, "https://example.com", "")
+if err != nil {
+  return err
 }
-
-_, err := info.DownloadThumbnail(ctx, t.TempDir(), 50, true)
-// assert err != nil
+fmt.Println(info.Title, info.Description)
 ```
 
-3) Simulate encoder failure when writing thumbnails (override `outputImage`):
+### Download image and thumbnail
 
 ```go
-origOut := outputImage
-defer func() { outputImage = origOut }()
-outputImage = func(dst *os.File, src *image.RGBA, format string) error {
-  return errors.New("simulated encode failure")
+imgPath, err := info.DownloadImage(ctx, "images", true)
+if err != nil {
+  return err
 }
 
-_, err := info.DownloadThumbnail(ctx, t.TempDir(), 50, true)
-// assert err != nil
+thumbPath, err := info.DownloadThumbnail(ctx, "thumbnails", 150, false)
+if err != nil {
+  return err
+}
 ```
 
-Notes:
-- Ensure your test imports include `errors`, `io`, `image`, and `strings` as needed.
-- Restore the original variables with `defer` to avoid cross-test interference.
-- These examples are intentionally minimal — adapt them to your test fixtures (httptest servers, temp dirs, etc.).
+### Public API
 
-4) Simulate HTTP client timeout by overriding `newHTTPClient`:
-
-```go
-origClient := newHTTPClient
-defer func() { newHTTPClient = origClient }()
-newHTTPClient = func() *http.Client {
-  // short timeout for test
-  return &http.Client{Timeout: 50 * time.Millisecond}
-}
-
-// then call DownloadImage which uses newHTTPClient()
-_, err := info.DownloadImage(ctx, t.TempDir(), true)
-// assert err != nil (expect timeout)
-```
+- `Fetch(ctx, rawURL, userAgent)` extracts metadata from a page.
+- `(*Webinfo).DownloadImage(ctx, destDir, temporary)` downloads `Webinfo.ImageURL`.
+- `(*Webinfo).DownloadThumbnail(ctx, destDir, width, temporary)` creates a resized thumbnail.
 
-### Error handling
+## Behavior notes
 
-The package uses `github.com/goark/errs` for wrapping errors with contextual keys (e.g. `url`, `path`, `dir`).
-Callers should inspect returned errors accordingly.
+- `Fetch` uses explicit precedence for metadata extraction:
+  - title: `title` -> `twitter:title` -> `og:title`
+  - description: `meta[name=description]` -> `twitter:description` -> `og:description`
+  - image: `twitter:image` -> `og:image`
+- `DownloadImage` resolves extension in this order:
+  1. URL path extension
+  2. response `Content-Type`
+  3. sniff first 512 bytes (`http.DetectContentType`)
+  4. fallback `.img`
+- `DownloadThumbnail` uses width `150` when `width <= 0`.
 
-### Tests & development
+## Error handling
 
-- Run all tests: `go test ./...`
-- The repository includes `Taskfile.yml` tasks for common workflows; see that file for CI/test commands.
+This package wraps errors with `github.com/goark/errs` and attaches context
+values such as `url`, `path`, and `dir`.
 
 ## Modules Requirement Graph
 
 [![dependency.png](./dependency.png)](./dependency.png)
 
-[webinfo]: https://github.com/goark/webinfo "goark/webinfo: Extract metadata and structured information from web pages"
+[webinfo]: https://github.com/goark/webinfo "goark/webinfo"
diff --git a/Taskfile.yml b/Taskfile.yml
index 4731e6a..1ac0e09 100644
--- a/Taskfile.yml
+++ b/Taskfile.yml
@@ -5,36 +5,29 @@ tasks:
     cmds:
       - task: prepare
       - task: test
-      # - task: nancy
+      - task: govulncheck
       - task: graph
 
-  build-all:
-    desc: Build executable binary with GoReleaser.
-    cmds:
-      - goreleaser --snapshot --skip=publish --clean
-
   test:
     desc: Test and lint.
     cmds:
       - go mod verify
-      - go test -shuffle on ./... -coverprofile=coverage.out -cover
-      - go tool cover -func=coverage.out
-      - govulncheck ./...
-      - golangci-lint-v2 run --enable gosec --timeout 10m0s ./...
+      - go test -shuffle on ./...
+      - golangci-lint-v2 run --enable gosec --timeout 3m0s ./...
     sources:
       - ./go.mod
       - '**/*.go'
 
-  nancy:
-    desc: Check vulnerability of external packages with Nancy.
+  govulncheck:
+    desc: Check reachable vulnerabilities with latest govulncheck.
     cmds:
-      - depm list -j | nancy sleuth -n
+      - go run golang.org/x/vuln/cmd/govulncheck@latest ./...
     sources:
       - ./go.mod
       - '**/*.go'
 
   prepare:
-      - go mod tidy -v -go=1.25
+      - go mod tidy -v -go=1.25.10
 
   clean:
     desc: Initialize module and build cache, and remake go.sum file.
@@ -52,3 +45,4 @@ tasks:
       - '**/*.go'
     generates:
       - ./dependency.png
+
diff --git a/errs.go b/errs.go
index 1b5cb02..92867d5 100644
--- a/errs.go
+++ b/errs.go
@@ -8,7 +8,7 @@ var (
 	ErrInvalidURL  = errors.New("invalid URL")
 )
 
-/* Copyright 2025 Spiegel
+/* Copyright 2025-2026 Spiegel
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/fetch.go b/fetch.go
index 8c59d45..0ec7812 100644
--- a/fetch.go
+++ b/fetch.go
@@ -15,39 +15,18 @@ import (
 	"golang.org/x/net/html/charset"
 )
 
-// Fetch retrieves metadata from the web page at urlStr and returns it as a *Webinfo.
+// Fetch retrieves metadata from a web page and returns it as Webinfo.
 //
-// Behavior:
-//   - Parses urlStr and performs an HTTP GET using the provided context (ctx).
-//   - If userAgent is empty, a default dummy User-Agent string is used.
-//   - Uses an HTTP client and sets the User-Agent request header.
-//   - Reads up to the first 1024 bytes of the response to detect the page character
-//     encoding via charset.DetermineEncoding (also considers the response Content-Type).
-//     If an encoding is detected or inferred by name, the response body is decoded
-//     accordingly before HTML parsing.
+// It fetches the page with the given context and User-Agent (or a default one when
+// empty), peeks up to 1024 bytes to determine encoding, then parses the head
+// section with goquery.
 //
-// Parsing and extracted fields:
-// - Parses the document head with goquery and extracts:
-//   - Title: from <title>, then overridden by meta[property="twitter:title"] or meta[property="og:title"] if present.
-//   - Description: from meta[name="description"], then overridden by meta[property="twitter:description"] or meta[property="og:description"].
-//   - ImageURL: from meta[property="twitter:image"] or meta[property="og:image"].
-//   - Canonical: from link[rel="canonical"].
+// Extraction precedence is kept explicit:
+// title: title -> twitter:title -> og:title
+// description: meta[name=description] -> twitter:description -> og:description
+// image: twitter:image -> og:image
 //
-// - The returned Webinfo contains at least:
-//   - URL: the original urlStr (string form).
-//   - Location: the final request URL (after redirects) from the response.
-//   - UserAgent: the User-Agent actually used.
-//
-// Error handling and resource cleanup:
-// - Network, URL parsing, encoding detection, and HTML parsing errors are wrapped with contextual information (including the URL).
-// - The response body is closed in a deferred function; any close error is joined with the returned error.
-// - On error, Fetch returns a nil *Webinfo and a non-nil error.
-//
-// Notes and guarantees:
-// - The first 1024 bytes are peeked (without advancing the reader) to determine encoding.
-// - DetermineEncoding's boolean return value is ignored (some encodings like Shift_JIS may be reported inconsistently); the detected encoding or a named encoding (via encoding.GetEncoding) is preferred.
-// - The function honors context cancellation for the HTTP request.
-// - Caller should assume that a non-nil *Webinfo is returned only on success; otherwise, info is nil.
+// Returned errors are wrapped with context. Response close errors are joined.
 func Fetch(ctx context.Context, urlStr, userAgent string) (info *Webinfo, err error) {
 	// check arguments
 	parsed, uerr := fetch.URL(strings.TrimSpace(urlStr))
@@ -158,10 +137,8 @@ func Fetch(ctx context.Context, urlStr, userAgent string) (info *Webinfo, err er
 	return
 }
 
-// getUserAgent returns a user-agent string to use for HTTP requests.
-// It trims whitespace from the provided ua parameter; if the trimmed value is empty,
-// it returns a default (dummy) User-Agent string ("Mozilla/5.0 (Windows NT 6.1; rv:11.0) Gecko/20100101 Firefox/11.0").
-// Otherwise, it returns the supplied ua unchanged.
+// getUserAgent returns ua if non-empty after trimming; otherwise it returns
+// the package default User-Agent string.
 func getUserAgent(ua string) string {
 	if len(strings.TrimSpace(ua)) == 0 {
 		return "Mozilla/5.0 (Windows NT 6.1; rv:11.0) Gecko/20100101 Firefox/11.0" //dummy user-agent string
@@ -169,7 +146,7 @@ func getUserAgent(ua string) string {
 	return ua
 }
 
-/* Copyright 2025 Spiegel
+/* Copyright 2025-2026 Spiegel
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/fetch_test.go b/fetch_test.go
index 2e061b5..a0c4c5c 100644
--- a/fetch_test.go
+++ b/fetch_test.go
@@ -277,7 +277,7 @@ func TestFetch_ISO2022JP_Encoding(t *testing.T) {
 	}
 }
 
-/* Copyright 2025 Spiegel
+/* Copyright 2025-2026 Spiegel
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/go.mod b/go.mod
index 8f3cfa3..8ebe869 100644
--- a/go.mod
+++ b/go.mod
@@ -1,15 +1,17 @@
 module github.com/goark/webinfo
 
-go 1.25
+go 1.25.10
+
+toolchain go1.26.3
 
 require (
-	github.com/PuerkitoBio/goquery v1.11.0
-	github.com/goark/errs v1.3.2
-	github.com/goark/fetch v0.5.0
+	github.com/PuerkitoBio/goquery v1.12.0
+	github.com/goark/errs v1.3.4
+	github.com/goark/fetch v0.5.3
 	github.com/mattn/go-encoding v0.0.2
-	golang.org/x/image v0.33.0
-	golang.org/x/net v0.47.0
-	golang.org/x/text v0.31.0
+	golang.org/x/image v0.40.0
+	golang.org/x/net v0.54.0
+	golang.org/x/text v0.37.0
 )
 
 require github.com/andybalholm/cascadia v1.3.3 // indirect
diff --git a/go.sum b/go.sum
index d9ec9e8..f65ed5a 100644
--- a/go.sum
+++ b/go.sum
@@ -1,11 +1,11 @@
-github.com/PuerkitoBio/goquery v1.11.0 h1:jZ7pwMQXIITcUXNH83LLk+txlaEy6NVOfTuP43xxfqw=
-github.com/PuerkitoBio/goquery v1.11.0/go.mod h1:wQHgxUOU3JGuj3oD/QFfxUdlzW6xPHfqyHre6VMY4DQ=
+github.com/PuerkitoBio/goquery v1.12.0 h1:pAcL4g3WRXekcB9AU/y1mbKez2dbY2AajVhtkO8RIBo=
+github.com/PuerkitoBio/goquery v1.12.0/go.mod h1:802ej+gV2y7bbIhOIoPY5sT183ZW0YFofScC4q/hIpQ=
 github.com/andybalholm/cascadia v1.3.3 h1:AG2YHrzJIm4BZ19iwJ/DAua6Btl3IwJX+VI4kktS1LM=
 github.com/andybalholm/cascadia v1.3.3/go.mod h1:xNd9bqTn98Ln4DwST8/nG+H0yuB8Hmgu1YHNnWw0GeA=
-github.com/goark/errs v1.3.2 h1:ifccNe1aK7Xezt4XVYwHUqalmnfhuphnEvh3FshCReQ=
-github.com/goark/errs v1.3.2/go.mod h1:ZsQucxaDFVfSB8I99j4bxkDRfNOrlKINwg72QMuRWKw=
-github.com/goark/fetch v0.5.0 h1:mZM4Gd3DfLXwrCjw/2rbUBnifW/vqihjV3HkGN3xKXI=
-github.com/goark/fetch v0.5.0/go.mod h1:hv29ebMJTGgOL5hdZ05xxEyfjChqCEXRHH+PNOKh6IE=
+github.com/goark/errs v1.3.4 h1:/+/xwF3UwXGxGGLurzBTaMMoryTBeaPfheJ1aW9cglA=
+github.com/goark/errs v1.3.4/go.mod h1:4xM7rorwYQlqh9kUhfKpC5P7VAJW2KfvuQpYnTaU0ek=
+github.com/goark/fetch v0.5.3 h1:ZwT5N04BSiPw2tF2gG5MXsmoSr+A/sxE52KJWy/aWzw=
+github.com/goark/fetch v0.5.3/go.mod h1:jgu+bn1HN8AfEks+ENqiPJVF99Cvs7cb2dqSujhjsOE=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/mattn/go-encoding v0.0.2 h1:OC1L+QXLJge9n7yIE3R5Os/UNasUeFvK3Sa4NjbDi6c=
 github.com/mattn/go-encoding v0.0.2/go.mod h1:WUNsdPQLK4JYRzkn8IAdmYKFYGGJ4/9YPxdPoMumPgY=
@@ -16,8 +16,8 @@ golang.org/x/crypto v0.13.0/go.mod h1:y6Z2r+Rw4iayiXXAIxJIDAJ1zMW4yaTpebo8fPOliY
 golang.org/x/crypto v0.19.0/go.mod h1:Iy9bg/ha4yyC70EfRS8jz+B6ybOBKMaSxLj6P6oBDfU=
 golang.org/x/crypto v0.23.0/go.mod h1:CKFgDieR+mRhux2Lsu27y0fO304Db0wZe70UKqHu0v8=
 golang.org/x/crypto v0.31.0/go.mod h1:kDsLvtWBEx7MV9tJOj9bnXsPbxwJQ6csT/x4KIN4Ssk=
-golang.org/x/image v0.33.0 h1:LXRZRnv1+zGd5XBUVRFmYEphyyKJjQjCRiOuAP3sZfQ=
-golang.org/x/image v0.33.0/go.mod h1:DD3OsTYT9chzuzTQt+zMcOlBHgfoKQb1gry8p76Y1sc=
+golang.org/x/image v0.40.0 h1:Tw4GyDXMo+daZN1znreBRC3VayR1aLFUyUEOLUdW1a8=
+golang.org/x/image v0.40.0/go.mod h1:uIc348UZMSvS5Z65CVZ7iDPaNobNFEPeJ4kbqTOszmA=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/mod v0.12.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
@@ -32,8 +32,8 @@ golang.org/x/net v0.15.0/go.mod h1:idbUs1IY1+zTqbi8yxTbhexhEEk5ur9LInksu6HrEpk=
 golang.org/x/net v0.21.0/go.mod h1:bIjVDfnllIU7BJ2DNgfnXvpSvtn8VRwhlsaeUTyUS44=
 golang.org/x/net v0.25.0/go.mod h1:JkAGAh7GEvH74S6FOH42FLoXpXbE/aqXSrIQjXgsiwM=
 golang.org/x/net v0.33.0/go.mod h1:HXLR5J+9DxmrqMwG9qjGCxZ+zKXxBru04zlTvWlWuN4=
-golang.org/x/net v0.47.0 h1:Mx+4dIFzqraBXUugkia1OOvlD6LemFo1ALMHjrXDOhY=
-golang.org/x/net v0.47.0/go.mod h1:/jNxtkgq5yWUGYkaZGqo27cfGZ1c5Nen03aYrrKpVRU=
+golang.org/x/net v0.54.0 h1:2zJIZAxAHV/OHCDTCOHAYehQzLfSXuf/5SoL/Dv6w/w=
+golang.org/x/net v0.54.0/go.mod h1:Sj4oj8jK6XmHpBZU/zWHw3BV3abl4Kvi+Ut7cQcY+cQ=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -70,8 +70,8 @@ golang.org/x/text v0.13.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
 golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
 golang.org/x/text v0.15.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
 golang.org/x/text v0.21.0/go.mod h1:4IBbMaMmOPCJ8SecivzSH54+73PCFmPWxNTLm+vZkEQ=
-golang.org/x/text v0.31.0 h1:aC8ghyu4JhP8VojJ2lEHBnochRno1sgL6nEi9WGFGMM=
-golang.org/x/text v0.31.0/go.mod h1:tKRAlv61yKIjGGHX/4tP1LTbc13YSec1pxVEWXzfoeM=
+golang.org/x/text v0.37.0 h1:Cqjiwd9eSg8e0QAkyCaQTNHFIIzWtidPahFWR83rTrc=
+golang.org/x/text v0.37.0/go.mod h1:a5sjxXGs9hsn/AJVwuElvCAo9v8QYLzvavO5z2PiM38=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
diff --git a/webinfo.go b/webinfo.go
index 8efecf9..ba9feae 100644
--- a/webinfo.go
+++ b/webinfo.go
@@ -22,18 +22,8 @@ import (
 	"golang.org/x/image/draw"
 )
 
-// Webinfo holds common metadata extracted from a web page.
-// It captures information useful for previews or link metadata:
-//
-// - URL: the original page URL.
-// - Location: the location declared by the page (if any).
-// - Canonical: the canonical URL declared by the page (if any).
-// - Title: the page title.
-// - Description: a short summary or meta description for the page.
-// - ImageURL: a representative image URL suitable for previews.
-// - UserAgent: the User-Agent string used to fetch the page.
-//
-// Fields may be empty or nil when the corresponding metadata is not present.
+// Webinfo stores metadata extracted from a web page and values used for
+// follow-up image download operations.
 type Webinfo struct {
 	URL         string `json:"url,omitempty"`         // Original page URL
 	Location    string `json:"location,omitempty"`    // Location
@@ -44,51 +34,18 @@ type Webinfo struct {
 	UserAgent   string `json:"user_agent,omitempty"`  // User-Agent used to fetch the page
 }
 
-// DownloadImage downloads the image pointed to by w.ImageURL and saves it to destDir,
-// returning the path of the saved file (outPath) or an error.
-//
-// Behavior:
-//   - The method is a receiver on *Webinfo and will return an error if w is nil or if
-//     ImageURL is empty.
-//   - ctx is used to control/cancel the underlying HTTP request.
-//   - destDir is cleaned with filepath.Clean. If it is non-empty, the directory (and any
-//     required parents) will be created with mode 0750. If destDir is empty, file
-//     creation uses the system/default behavior for temporary or current directories.
-//   - If `temporary` is true, the image is written to a temporary file (created via
-//     the package-level `createFile` helper which wraps `os.CreateTemp`) and the
-//     temporary file path is returned. If the URL path does not contain a filename,
-//     `temporary` is forced true.
-//   - If `temporary` is false, the image is written to `destDir` with the filename
-//     taken from the URL path. If the URL filename has no extension, an extension is
-//     appended (see extension resolution below). Existing files will be truncated by
-//     the underlying `createFile`/`os.Create` behavior.
+// DownloadImage downloads w.ImageURL and writes it under destDir.
 //
-// HTTP download and content-type/extension resolution:
-//   - The image is fetched using an HTTP GET performed with the provided context; the
-//     request User-Agent is set via getUserAgent(w.UserAgent).
-//   - Extension resolution order:
-//     1) Extension from the URL path (if present).
-//     2) Extension(s) derived from the Content-Type response header via mime.ExtensionsByType.
-//     3) If still unknown, the first up-to-512 bytes of the body are read and
-//     http.DetectContentType is used to guess the content type, then mime.ExtensionsByType.
-//     4) If no extension can be determined, ".img" is used as a fallback.
-//   - When bytes are sniffed from the body, they are prepended back to the reader so the
-//     full image is written to disk. When multiple extensions are returned by
-//     mime.ExtensionsByType the implementation picks the last returned extension.
-//   - File creation is performed via the package-level `createFile` variable which tests
-//     may override to simulate create failures.
+// If temporary is true, or if the URL path has no filename, a temporary file is created.
+// Otherwise the output file name is derived from the URL path.
 //
-// Resource management and errors:
-//   - The response body and any created file are closed using deferred cleanup; any close
-//     errors are joined into the returned error.
-//   - I/O, network and OS errors are returned (wrapped with contextual information).
-//   - On success, outPath contains the absolute/relative path to the saved image file;
-//     on error, outPath will be empty and err will describe the failure.
+// Extension resolution order is:
+//  1. URL path extension
+//  2. response Content-Type
+//  3. sniffed content type from up to 512 bytes
+//  4. fallback ".img"
 //
-// Notes:
-//   - The function may truncate an existing destination file with the same name.
-//   - The exact behavior of temporary file placement when destDir is empty follows the
-//     semantics of os.CreateTemp.
+// Returned errors are wrapped with context and include cleanup failures.
 func (w *Webinfo) DownloadImage(ctx context.Context, destDir string, temporary bool) (outPath string, err error) {
 	if w == nil {
 		err = errs.Wrap(ErrNullPointer)
@@ -212,50 +169,16 @@ func (w *Webinfo) DownloadImage(ctx context.Context, destDir string, temporary b
 	return
 }
 
-// DownloadThumbnail downloads the image referenced by the Webinfo receiver, scales it
-// to the requested width (preserving aspect ratio), and writes the resulting thumbnail
-// image to disk.
+// DownloadThumbnail downloads the source image, resizes it to width while keeping
+// aspect ratio, and writes the thumbnail to destDir.
 //
-// The method returns the path to the created thumbnail file or an error. Behavior details:
-//   - If the receiver is nil, ErrNullPointer is returned.
-//   - If width <= 0, a default width of 150 pixels is used.
-//   - destDir is cleaned and, if non-empty, created with mode 0750 (os.MkdirAll).
-//   - The original image is always downloaded to a temporary file via DownloadImage(..., true).
-//     That temporary original file is removed when the function returns (even on error).
-//   - The original image file is opened and decoded. If decoding fails, an error is returned.
-//   - The thumbnail height is computed to preserve aspect ratio: newH = round(width * origH / origW).
-//     newH is clamped to at least 1 pixel.
-//   - The image is resized using a Catmull-Rom resampler into an RGBA image of size
-//     width x newH.
-//   - The output format/extension is chosen from the decoded format: jpeg/jpg → .jpg, png → .png,
-//     gif → .gif. Unknown formats fall back to PNG.
-//   - If `temporary` is true, the thumbnail file is created via the package-level
-//     `createFile` helper (which wraps `os.CreateTemp`) in `destDir` using the
-//     pattern "webinfo-thumb-*<ext>"; the temporary file path is returned.
-//   - If `temporary` is false, the output filename is derived from the original image
-//     URL basename (falling back to "webinfo-image") and named "<base>-thumb<ext>" in
-//     `destDir`.
-//   - The encoder used to write the thumbnail is the package-level `outputImage` function
-//     variable; tests may replace this variable to simulate encoder failures. The image
-//     decoding step uses the package-level `decodeImage` wrapper around `image.Decode`,
-//     which tests may also override.
-//   - Files are properly closed with deferred cleanup; any close/remove errors are joined into
-//     the returned error using the errs package.
-//   - All filesystem, download, and image-processing errors are wrapped with contextual
-//     information (e.g., paths, URL) before being returned.
+// width defaults to 150 when width <= 0.
 //
-// Parameters:
-//   - ctx: context for cancellation and timeouts passed to DownloadImage and other operations.
-//   - destDir: destination directory for the thumbnail (cleaned). If empty, creation uses the
-//     current directory semantics of os.Create/os.CreateTemp.
-//   - width: desired thumbnail width in pixels (defaults to 150 if <= 0).
-//   - temporary: if true, create a uniquely-named temporary file; otherwise create a stable
-//     filename based on the original image basename.
+// The source image is downloaded to a temporary file first and removed on return.
+// Output uses a temporary name when temporary is true; otherwise it uses
+// "<base>-thumb<ext>" derived from the original image URL.
 //
-// Returns:
-//   - outPath: filesystem path to the created thumbnail file (valid when err == nil).
-//   - err: non-nil on failure; common failure reasons include download errors, decode errors,
-//     filesystem errors, and invalid image dimensions (ErrNoImageURL).
+// Returned errors are wrapped with context and include cleanup failures.
 func (w *Webinfo) DownloadThumbnail(ctx context.Context, destDir string, width int, temporary bool) (outPath string, err error) {
 	if w == nil {
 		err = errs.Wrap(ErrNullPointer)
@@ -377,9 +300,8 @@ func (w *Webinfo) DownloadThumbnail(ctx context.Context, destDir string, width i
 	return
 }
 
-// outputImage encodes the provided *image.RGBA src and writes it to dst using
-// the encoder corresponding to the given format string. It is a variable so
-// tests can replace it to simulate encoder failures.
+// outputImage writes src to dst using format-specific encoders.
+// Tests may replace this variable.
 var outputImage = func(dst *os.File, src *image.RGBA, format string) error {
 	switch format {
 	case "jpeg", "jpg":
@@ -392,9 +314,8 @@ var outputImage = func(dst *os.File, src *image.RGBA, format string) error {
 	return png.Encode(dst, src) // default to PNG
 }
 
-// createFile is a package-level helper used to create files. It abstracts
-// the creation of temporary and permanent files so tests can replace it to
-// simulate failures during os.Create/os.CreateTemp.
+// createFile creates temporary or permanent files.
+// Tests may replace this variable.
 var createFile = func(temp bool, dir, pathOrPattern string) (*os.File, error) {
 	if temp {
 		return os.CreateTemp(dir, pathOrPattern)
@@ -402,21 +323,19 @@ var createFile = func(temp bool, dir, pathOrPattern string) (*os.File, error) {
 	return os.Create(filepath.Clean(pathOrPattern))
 }
 
-// decodeImage is a package-level wrapper around image.Decode so tests can
-// replace it to simulate decoding behaviors (e.g., returning zero-dimension
-// images) without modifying stdlib functions.
+// decodeImage wraps image.Decode.
+// Tests may replace this variable.
 var decodeImage = func(r io.Reader) (image.Image, string, error) {
 	return image.Decode(r)
 }
 
-// newHTTPClient returns the http.Client used for web requests. It is a package-level
-// variable so tests can override it. By default it sets a 30-second timeout for
-// the whole request (connect+read+write).
+// newHTTPClient returns the default HTTP client used by downloads.
+// Tests may replace this variable.
 var newHTTPClient = func() *http.Client {
 	return &http.Client{Timeout: 30 * time.Second}
 }
 
-/* Copyright 2025 Spiegel
+/* Copyright 2025-2026 Spiegel
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/webinfo_test.go b/webinfo_test.go
index 20f1b1c..241759b 100644
--- a/webinfo_test.go
+++ b/webinfo_test.go
@@ -187,7 +187,7 @@ func TestDownloadImage_TemporaryWhenNoFilenameAndContentType(t *testing.T) {
 		t.Fatalf("tmp file not created in dest: %s", out)
 	}
 	ext := filepath.Ext(out)
-	if ext != ".jpg" && ext != ".jpeg" && ext != ".img" {
+	if ext != ".jpg" && ext != ".jpeg" && ext != ".pjpeg" && ext != ".img" {
 		t.Fatalf("unexpected extension %q", ext)
 	}
 	got := readFile(t, out)
@@ -1068,7 +1068,7 @@ func TestDownloadThumbnail_TemporaryDefaultDest(t *testing.T) {
 	}
 }
 
-/* Copyright 2025 Spiegel
+/* Copyright 2025-2026 Spiegel
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.