If you're able to, go into your browser's developer tools / inspect element. Check the console and let me know if there are any errors in there. Something probably threw an error and thus the ready state isn't firing.
OK I checked and didn't see any errors and I did get in after a few re-freshes and closing out the browser and coming back. Looks like its running now.
Just thought I would bring attention to this just in case the issue pops up elsewhere.
It hasn't happened on my end before, though sometimes it will run a little slow if the template cache has to re-populate. Also check the network tab if you get a chance when it happens and see if any particular JS files are taking a while to download.
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#5912 - Please wait for the page to load then try again. On site enterance to log in.
Just thought I would bring attention to this just in case the issue pops up elsewhere.
The errors I see are attached below.
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