Cannot update settings - progress bar hangs

I cannot update any settings. The purple progress bar simply hangs.

To replicate:
Go to settings page.
Change menu name.

Click update settings.

Expected:
Spinning wheel in update button, purple progress bar at top of page rapidly crosses the screen, progress button resets, some sort of success message, menu name successfully changed.

ACTUAL:
Spinning wheel in update button, purple progress bar starts to cross screen, slows down to a crawl, after several minutes seems to make it almost across - but button never resets and nothing happens.
Refreshing the screen shows no changes have been registered.

Tried with no plugins other than WooCommerce and WooBase active.

Tried clearing caches.

WP 6.6
WooCommerce 9.1.2

WooBase 1.0.9

Please advise.