Not sure if this is the right place for an Edge problem.

I started my laptop a few days ago only to find most of my Edge favourites had gone.
Soon after that Edge closed down and will now only start for 2 or 3 seconds before closing itself so no chance to clean the cache or disable extensions.

I've done a system restore, though surprised I only had one option from a week ago even though I do them regularly, but the restore didn't help.

I’ve run the DELL support app plus Windows Defender plus Total AV plus Malewarebytes but no change

After Googling I tried the sfc /scannow thing but no help.

I’ve tried modify/repair Microsoft Edge but no difference.

Using Windows 10.

Any ideas?