Glyphs app is very slow when an image imported

Hello, when I import an image one of my drawings to draw letters. The app is being too slow while editing nodes, using pen tool, etc.
Does anyone experience this?

Which app/OS versions? And which hardware are you using?

And how big is the image?

1300/High Sierra (10.13.6).
I am using a wired mouse
GPU: Intel Iris Plus Graphics 640 1536 MB
CPU: 2,3 GHz Intel Core i5

image dimensions: 3390 × 2478 / 300 dpi
I have also tried 1368 x 1000 / 72 dpi but still slowing down.

Can you send me the .glyphs file and the image?

Sent to support (at) (this website without www)
This is the correct mail adress right?

Got it.

If you right click the image and click “Set Crop to Layer bounds” it should be a bit faster. And in the same context menu, click “Lock Image” that you don’t select it accidentally.

Yes I have been using the “Lock Image” feature but the other one did some improvement though still not as fast as when no image imported.

Thanks for the help!