3.0.4 on MacOS 10.12.4 : hangs at the entrance

After upgrading to 3.0.4 (MacOS 10.12.4) I could not enter Glyphs.
The cursor just spins and that’s it.
Screen Shot 2021-12-18 at 00.58.58

So far back to 3.0.3.

Could you try starting it with the Option and Shift key pressed?
You can have two versions side by side. Duplicate the app and rename it to ‘Glyphs 3.0.4’. Then open this one and update it.

I will try to do as you described
Thank you