Not kotlin, but ouch… upgraded to 2021.2 Ultimate via the Toolbox. A lot of plugins not working; but oddly they do have 2021.2 versions on the plugins page. Check for updates not updating them. Seems like IntelliJ is failing to spot the available upgrade?
e.g., I have the
.ignore
, a JetBrains plugin installed at v 4.1.0. It reports