I have the same issue now. An experiment that worked fine yesterday afternoon is now stuck on the same white initialising the experiment page (edit: the experiment from yesterday actually “works” but it gets overwritten by an older version now, from 23/7, somehow. however many times I sync it does not update.)
I’ve tried a million things to resync, but an old file keeps overwriting it so I created the experiment anew under a different name and folder, to get a fresh repo in gitlab - and this new one has the same “initialising the experiment…” page you describe. Wondering if anything changed overnight @jon?
(link of newly created exp: https://run.pavlovia.org/cc99/newcd/html/ - works fine locally, and yesterday’s file which is overwritten by an other file, here https://run.pavlovia.org/cc99/jul29spsyexp/html/)
Please see also Issues getting started for I think a better explanation.