@donq said in The Option, To Re-Show A Previously Hidden Extension Icon In The Extension Toolbar, No Longer Exists:
Well, I just discovered that my Opera (dev version, but most likely earlier ones included that too) has a little cube-shaped button after extensions icons (before Downloads one), tooltipped (is that a word?) as 'Extensions'. Clicking it opens popup with a list of installed and enabled extensions, where you can pin and unpin them Problem solved, at least for me.
I don't think that worked for me but to follow up on what I posted before: I realized that I can click and drag the extensions from the drop down menu I mentioned before with the two arrows. At this point the problem is solved for me. And the option within the extensions menu to "hide from toolbar" actually was working, despite what I originally thought, but it works differently from how I thought it did. It actually completely removes the extension from the toolbar, rather than hiding it in the menu like chrome does.