The Sticky Titles Tweak is v. popular.
But it can visually fail if you have any top bar that would overlay it.
For instance on tw.com they don’t work properly if switched to “yes”.
Sticky Titles don’t have, as far as I can see, a configurable “vertical offset” setting.
But you can manually add any needed vertical offset by editing $:/themes/tiddlywiki/vanilla/sticky …
TT