I have this too, but with Slack and Nautilus. Steps to reproduce:
1. Have someone send you a file on Slack. 2. Download the file and click on "Open containing folder". 3. The opened Nautilus window is now grouped with the Slack icon on the launcher.
I have this too, but with Slack and Nautilus. Steps to reproduce:
1. Have someone send you a file on Slack.
2. Download the file and click on "Open containing folder".
3. The opened Nautilus window is now grouped with the Slack icon on the launcher.