Probably not using the same client, but there might be something related to “floating button” or a setting in comments appearence.

Settings > Fuckin Things > This Fuckin Thing > Off

Settings shortcut: Comment options > Display navigation bar

Click on that 👆, it will take you to the setting that you need to turn off.

Ooh, I like being able to jump from top comment to top comment. Imma go enable that