When there's a failing test, the indicator turns red:

When I fix it, the comment disappears, but the indicator is still red:

oh yeah, that's weird, I've not seen this before - can you clone the repo and have a look with the debugger at the status of that it? Is there two wit the same name by any chance?
When you fix it, are the files you're modifying back to an unchanged state in git (unstaged/uncommited)?
I've seen one case if you fix and either commit, or the fix goes back to unchanged state. Jest is only acting on unstaged/uncommited files and as a result the editor doesn't currently update the decorators for files it thinks have no changes.
We made some improvements here, if you're still seeing the issue feel free to reopen.
Still seeing this with latest version
I've also seen variations of this as well. I'm going to try to find some time to track down the specific repro and hopefully fix. Basically there's some cases where the decorators aren't updating when they should.
Same problem here with vscode 1.16.1 and Jest extension 2.4.2 under Linux:

I've seen this occur in the following scenario:
Likely related/same as https://github.com/jest-community/vscode-jest/issues/32?
@daldridge-cs I noticed the same thing and it has been reported here: #308
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@daldridge-cs I noticed the same thing and it has been reported here: #308