Old version banner not discoverable on headings links.

[mikkelhegn]

Ref #1421: @karthik2804 - the banner is not visible on a headings link - like this: https://developer.fermyon.com/spin/v2/manifest-reference#the-variables-table - is that something we can fix?

[karthik2804]

We could make it a sticky to the top something like

Or we could stick it the side menu which will not be visible on mobile though. Or we could end up adding a floating button. I am not sure what is the best solution in terms of UX. cc: @flynnduism