Gmail Quote Collapser by Naftali

Gmail Quote Collapser helps clean up email conversations in the places where Gmail’s built-in quoted-text collapsing does not work well.

Gmail already hides quoted message history correctly in many conversations, so in those messages you may not notice any change at all. This extension is designed for the exceptions — messages where repeated or quoted email history remains visible and makes the conversation unnecessarily long or difficult to read.

You can create custom text rules that tell the extension where quoted or repeated content begins. When one of those rules matches a Gmail message, Gmail Quote Collapser collapses that portion of the message while still allowing you to expand it whenever you want.

Rule sync is optional and off by default. Your rules stay on the computer where you created them unless you enable sync.

To use the same rules on your other Firefox desktop devices, open Gmail Quote Collapser’s settings and click Enable Firefox rule sync. Firefox will then ask for your permission before any rule data is synced through Mozilla’s Firefox Sync service.

Rule markers may contain names, email addresses, or copied email text. Gmail message bodies themselves are processed locally in your browser and are not synced or sent to any developer-operated server.

The extension does not delete emails or remove content from Gmail. It only changes how matching quoted history is displayed in your browser.