Documentation
Theme Drift: Compare & Diff
How it works
Pick your themes
Choose two themes, or three if you want your edits told apart from the update. Every theme in the store is available.
Read the file list
Each file gets one clear status and a colour that means only that. Conflicts come first, unchanged files last.
Open a file and decide
The side by side view highlights the words that actually differ, so you can copy what you want into the theme editor.
What each status means
Conflict
You and the theme developer both changed this file, differently. Start here.
Your change only
Only you touched it. The update leaves this file alone, so nothing is at risk.
Changed in new version
The update changed it and you never did. Safe to take as is.
Already the same
You already made exactly the change the update makes. Nothing to do.
Deleted
The file is gone on one side, either removed by you or dropped from the theme.
Unchanged
Identical everywhere. Kept in the list so the count always adds up.
Free vs. one-time unlock
Always free
- Standard 2-theme comparison, line by line detail included
- Run 3-way comparisons as often as you like
- Full file list in 3-way, one clear status per file, plus filters
- Image, video and file previews in standard comparison
One-time unlock ($9.99, no subscription)
- Open any file from a 3-way result with all three themes at once
- Conflicts show your edit and the update against the original
- Word level highlighting of what actually differs
- Added and removed line counts for each file
Frequently asked questions
Does this app change or merge my theme files?
No. It only reads and compares. There is no merge, apply or publish button anywhere, so a comparison can never break your live theme. When you decide a change is worth keeping, you copy it over yourself in the theme editor.
What exactly is a conflict?
A conflict is a file that both you and the theme developer changed, in different ways. Those are the files where you have a decision to make: keep your version, take the new one, or combine them by hand. Conflicts always sit at the top of the result list.
When should I use 3-way instead of standard?
Use 3-way whenever a new version of your theme is out and your live theme is customized. It compares the version you originally installed, your live theme and the new version together, which is the only way to tell your own edits apart from the developer's update. Standard mode is for plain two theme checks, like comparing a draft copy to the live one.
Do you keep a history of my comparisons?
No. Every comparison runs on demand against the files as they are right now, and nothing is stored afterwards. There is no automatic monitoring, no snapshots and no background jobs.
Why can some files not be opened?
Unchanged files are identical on every side, so there is nothing to open. Added, removed or changed images, videos, fonts and other assets open as a side-by-side preview. Text files open as a line-by-line diff.
Which file types are compared?
Every file in the theme: Liquid templates and sections, JSON templates and locales, CSS and JavaScript, plus images, videos, fonts and other assets. Text files open as a highlighted line-by-line diff. Media and other binaries open as a side-by-side preview.