For wysiwyg (html) fields, the formatting toolbar should be sticky. We use a few of these fields to manage some legal documents, which are long. If you want to format something you have to highlight it, scroll all the way back up to get to the formatting toolbar, and then scroll back down to where you were. Thanks!
Not really a solution but you can leverage keyboard shortcuts to work around the issue: https://www.tiny.cloud/docs/advanced/keyboard-shortcuts/#editorkeyboardshortcuts