WowAce

What version of Grid2 are you using?

 r871

What game client version (windows or mac) and language are you using ?

 Mac 10.14.2

What steps will reproduce the problem?

 Just do regular healing in a raid. It's more obvious in 25 man raid. But I can notice the FPS randomly drops even in island exp.
Did you try having Grid2 as the only enabled addon and everything else disabled?

  No. 

Was it working in a previous version? If yes, which was the last good one?

  I switched back to r868 then the issue is gone. Then I updated it to r871 the problem showed up again. Then I switched it back to r868 again and things back to normal. I didn't test r869 and r870 yet. I'll fill in the detail after I test it.

Do you have an error log of what happened? If you don't see any errors, make sure that error reporting is enabled (`/console scriptErrors 1`) or install [BugSack](https://mods.curse.com/addons/wow/BugSack).

  No. There is no lua errors.

Please provide any additional information below.

Strange, there is not important changes between 871 and 868, Could you test version 870-alpha ?

If 870 works well, you can try disabling the mana indicator in version 871.

Tested the r871 version again in raid and it seems running normal now. Before the test WOW client got an automatically update and I restarted the computer. Either one fixed the issue I guess. Sorry about the false alarm.