When there’s no select range, the “fit selection” button is grayed-out. I suggest in that situation it convert to a “center start cursor” button. This would make it quick and simple to get back to where you started expanding the waveform and scrolling.
An intuitive way of jumping to the start and end of a select range after extreme expansion would also be useful, especially to novice users. My method is ‘Selection Extend Left’/‘Selection Contract Left’ to jump to the start of the select region, and ‘Selection Extend Right’/‘Selection Contract Right’ to jump to the end. I do this often when I’m matching waveforms before deleting a chunk. It took me a while to get used to these operations.
A workaround for this is to Fit Project then repeatedly zoom in. Once the cursor is on the screen zooming will centre on the cursor.
Nice workaround! But actually, I think that SHIFT+left arrow and SHIFT+right arrow are pretty intuitive already. Too bad they change the selection, though. Perhaps ALT-left arrow and ALT-right arrow would make sense.