GTMDiff

A Chrome Devtools extension for highlighting differences in custom code of GTM tags

Installation options

Drop the gtmdiff.crx file into the extensions page (chrome://extensions/)
Clone the repository and load the unpacked extension in the extensions page (chrome://extensions/)
[COMING SOON] Install the extension from the Chrome Web Store

Usage

Open a code diff screen in GTM
Open DevTools
Click on the GTMDiff tab