I think this is a bug; if not a bug, it might be an aberration.
I operate an application under the presumption that I should be able to do anything that I think it is reasonable to do with that application; in this case, scroll to the left or right.
I am editing a ten-minute track. The audio cursor is at 00:00:00 and I tap the space bar to begin the playback. Playback begins and my dulcet tones fill my little studio.
I have previously edited the preamble (name of book, chapter, public domain and so on), so I want to skip ahead about twenty seconds, which is the horizontal size of the pane at this zoom factor.
I have three options:-
(1) Drag the slider; I would rather not do this since this requires a precision of analogue movement, a weak skill.
(2) Click once in the space between the slider and the right-hand end of the scroll bar. This I prefer; it is a digital/discrete action and should move me exactly one pane-width to the right, which is, after all, what I want
(3) Click-and-hold on the caret at the right hand end of the scroll bar. I dislike this as for (1) because again it requires an analogue action - the duration of my hold-down time on the mouse.
The track has ten seconds of audio on it, there is plenty of stuff off to the right-hand side.
When I am at the left-hand (starting) end of a track this action(2) seems not to work. It is as if there is a solid brick wall which inhibits movement.
I may have understood the trick, but once I am past the first (zoom) pane of track, using a single-click between the slider and either end of the scroll bar (action 2) works as it has for me over the past 30 years in all Windows applications. Right down to Notepad.exe.
I have been observing this behaviour of Audacity 3.1.3 for two or three weeks now, on a new track each day (I am up to Section 48, each section being 30-60 minutes of spoken audio).
I do not consider this a crippling feature, more an annoyance.
That said, if there is a minor infraction in the program code, my experience has taught me that the infraction may reverberate through the program. (Typically: when a counter has not been initialized, chances are storing that the programmer(s) have not initialized other counters).
(signed) “Still in love with Audacity” of Bonavista.