Other extensions, particularly extensions that also track email opens and extensions that can be used to block tracking such as Virtru, Boomerang, CloudHQ, Ghostery, GMass and uBlock Origin, may conflict with the Mailtrack.
If Mailtrack is not working and you suspect that it may be due to a conflict with another extension then try the following:
1) Disable one of the other extensions installed on your browser.
2) Refresh the Gmail page.
3) Send a test tracked email to see if our tracking is working.
4) If necessary, repeat points 1-3 with each extension installed on your browser until you identify which extension is causing a conflict.
There aren't any compatibility standards for extensions and so as a result conflicts between extensions are quite common. When two extensions are incompatible with each other it is the responsibility of both parties to find a solution. At Mailtrack we work to make sure that our extension is compatible with popular extensions (ones that have millions of users) and extensions that our users request that we be compatible with.