ome6a1717 if you use Chrome, you could try to delete the cache storage in the application cache.
Press F12 then click on the tab Application. On the left of the debug-window should be 'Cache Storage' and it should have a little arrow. Click on the arrow and you should see all Construct3 version that are cached ,with right click you can delete the older one, but be careful and if you are in doubt, don't delete anything.
No clue if that is really your problem, but maybe it will help.