Usually, if you click an entry in your installed addons list, it will take you to that addons details and the back button will bring you back to the addon list.
If you howerver start an addon update that is still running in the background while you switch to addon details (occured with details for another addon, not tested with same one as being updated), the back button will break (maybe after the update finished and the list would be refreshed?) and take you to the addon descriptions Overview instead.
steps to reproduce:
have at least one updateable addon installed (preferably a larger one to increase the time frame)
have another addon in the list
(may not be needed)
trigger the update for the first addon
switch to the addon details of the second addon
switch to a sub-tab, e.g. changelog
(may not be needed, but helps to see where the back button takes you)
wait for the update to finish in background
use the back button
similar scenarios not (yet) tested:
using the back button while the update is still running
using details of the addon being updated
The back button should still take you back to the addon list since that's the page you came from.