Had some issues yesterday too. Might be itch... so try it later.
If the problem remains, tell me what version you last played and everything was OK. Plus device and browser.
262 days ago(+1)
IM BACK and it still doesnt work T-T im on a laptop and using just normal google and the last version i played was 1.4 so idk whats wrong..
261 days ago (+2)
Clear cache, free up to 900MB(here I specify with a large margin, so you may need less) of disk space so that Google can use it to run the game, reboot the device.
If it stucks at 90% again, wait a little longer without letting the device go to sleep. Another option is to reset the download, reload the page and restart the game (I find it strange, but it helps sometimes).
Also there will be an update on the 19th, so the situation may change.
Нope my recommendations help. Stay tuned!