Failed to execute the [toc] macro. Cause: [The execution of the [velocity]

The dropdown on the blue button should have something like Uninstall or Remove (can’t recall the right word ATM).
But maybe upgrading will fix your issue, you may give it a try.

After uninstalling it you may still get errors, you’ll have to restart your instance: Toc entries lose a parenthesis - #5 by watery