Steps to Reproduce:
This does not appear to affect any of the default activity bar icons.
Opened https://github.com/Microsoft/vscode/issues/54495
Although if you want to completely turn off the activity bar icon, you can either move the explorers into another location (explorer, source control, etc), or disable them completely.
See here, via the GitLens interactive settings editor

Closing this as this will be fixed in the August 2018 release of vscode (you can see it today with the insiders build of vscode).
Opened microsoft/vscode#54495
Although if you want to completely turn off the activity bar icon, you can either move the explorers into another location (explorer, source control, etc), or disable them completely.
See here, via the GitLens interactive settings editor
Where is that screenshot from? How do you get to that settings page in VSCode?
From the command palette, type _GitLens: Open Settings_
This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.
Most helpful comment
Opened https://github.com/Microsoft/vscode/issues/54495
Although if you want to completely turn off the activity bar icon, you can either move the explorers into another location (explorer, source control, etc), or disable them completely.
See here, via the GitLens interactive settings editor
