I almost filed this as a bug report:
1) Issue browser displays <n> TODO issues
2) Open a file with a TODO issue, remove that issue and save the file, but leave it open
3) Close and re-open issue browser - it still displays the issue you just deleted
It only displays the correct results AFTER the file (from which the issue has been removed) has been closed.
Issue Browser refresh issues
Issue Browser refresh issues
PB 5.73 on Windows 10 & OS X High Sierra