PR Screenshots
Screenshots in a PR are QA evidence. Each one shows what the real product renders at one location, framed so a reviewer who has never opened the page can tell what changed.
Step 1: List the Locations
List every place in the product that the diff reaches: each page, drawer, modal, or widget that renders a changed component, found by tracing its callers and consumers. Then add the states the change affects at each of them, such as loading, error, empty, hover, selected, menu open, expanded, scrolled, narrow viewport, and light or dark theme.
Never group surfaces into one row: for example, "GridEditable, as in Discover, dashboards and insights" is three rows.
Step 2: Capture From the Real Product
| Rule | Detail |
|---|---|
| Real build only | Screenshot the running app on the PR branch for "after" and on the base branch for "before". Never screenshot a story, mock page, or harness built for the PR, unless the change is to that story. |
| No injected changes | Never inject CSS or change the DOM to imitate the change. Stubbing API responses is fine; the frontend code must be the real code. |
| Seed missing data | If a state needs data no account has, create it in a local environment. Do not report a location as impossible to screenshot until seeding has been tried, and then say exactly what failed. |
| Identical framing | Capture the same region at the same dimensions for both shots of a pair, even when one state is taller. Emulate a fixed viewport instead of resizing the user's own browser window. |
| Context | Keep the heading or label that names the thing, nearby rows or controls, and a little padding on every side. For a hover, focus, or open-menu state, keep the trigger and the overlay in one frame. When the bug only makes sense in its page, show more of the page. |
| No empty bands | Crop out browser chrome, app navigation, and regions the change does not touch. For full-width layouts, shrink the viewport instead of leaving wide blank space beside short content. |
Step 3: Redact and Audit
- Blur only private values: emails, usernames, customer or organization names
and slugs, IDs, and internal hostnames. Keep keys, labels, and non-sensitive
values readable, such as
browser.name→chrome. - Paint over each region before blurring it so the blur can't be reversed. Never use solid black or dark boxes, and never blur whole tables or rows.
- Read every image before uploading it and check for credentials: tokens, auth headers, cookies, signed URLs, secret keys, and webhook endpoints. Remove real leaks. Do not treat a public client DSN as a leak.
Step 4: Choose the Table Shape
| Change | Shape |
|---|---|
| Visual change to existing UI | Changed table, plus an Unchanged table for locations the diff reaches that render the same. |
| New page or feature | No before/after. A few "after" screenshots, each introduced by a short sentence. When the new UI appears in several locations, use a Location | Screenshot table instead. |
| Alternatives with no "before", such as prototype treatments or design options | Treatment | Screenshot table, one row per alternative. |
| A change that differs by theme | Add a light and a dark row for each location, such as Explore › Logs, dark. For new UI, use Light | Dark columns instead. |
Pixel-diff every before/after pair. Move a pair with no visible difference, including anti-aliasing noise, to Unchanged with one image. Leave out a table that would be empty.
**Changed**
| Location | Before | After |
| --- | --- | --- |
| Explore › Logs |  |  |
| Explore › Logs, loading |  |  |
**Unchanged**
| Location | Before & After |
| --- | --- |
| Trace view › Logs |  |
Formatting rules:
- Name the first column
Location, orTreatmentfor alternatives. Never leave its header empty. - Write each location as a
›breadcrumb of what the reader clicks through, then a comma and the state:Monitors › cron monitor details › Check-Ins, loading. - Use only the columns shown above. Never add a "What changed" or notes column; the screenshots show the change.
- Give each image alt text naming its row and side, such as
Explore › Logs before. - Label the tables with bold
**Changed**and**Unchanged**lines. Do not add an intro sentence describing where or how the screenshots were taken. - Use Markdown tables by default, because
gh --attachrewrites only Markdown image references. Switch to an HTML table only when cells must span rows, such as a light and dark row under one location (Location | Theme | Before | Afterwithrowspan="2"on the location cell). Do not addalignattributes.
Step 5: Upload With gh
gh pr create, gh pr edit, gh pr comment, and the matching gh issue
commands accept --attach '<path>#<alt text>' (gh 2.99.0+). If gh rejects
the flag, ask the user to upgrade it. Do not push asset branches, commit
images, or upload through the browser's comment box.
Write the body file with relative Markdown image references, then pass the same
paths to --attach. gh uploads each file and rewrites the matching reference
to the uploaded URL in place:
gh pr edit 123 --body-file pr-body.md \
--attach './shots/logs-before.png' --attach './shots/logs-after.png'
| Behavior | Detail |
|---|---|
| Paths | Resolve against the current directory, and must match the body's references exactly. |
| Unreferenced attachments | Get appended to the end of the body as . |
| No body flag | gh pr edit --attach keeps the existing body and appends the images. |
| HTML tables | <img src="./x.png"> is not rewritten. Attach first, copy the appended URLs into the <img> tags, delete the appended lines, then write the final body with --body-file. |
Before writing a body the user may have edited, fetch it again and compare it with the version you last read. Keep the user's wording and table edits, swap in only your rows and URLs, and keep the body's line endings. Removing an image from the body does not delete the uploaded file.
Step 6: Keep Screenshots Current
When a later commit changes what a screenshot shows, retake the affected pairs, re-check which pairs belong in Changed and Unchanged, and update the body without waiting to be asked.