"checking" tab won't finish booting

Hello! I keep getting a “checking” tab every time I open the anki app on my desktop. It doesnt allow me to close it nor use the anki app itself. I have tried several things to fix it:

  1. uninstalled from mac and re-downloaded the new version
  2. Force quit and open again
  3. delete some cards directly from the ankiweb incase there was a card overload

Does anyone have advice on how I could correct this?

Please try holding down the shift key when you start Anki.

This worked! Thanks so much!