Tried disabling the mail/cal client and see if it still does it in barebones Vivaldi?
I recently had to disable mail on an instance in a Windows machine. As I had a few accounts on it to test functionality a few weeks ago, I had forgotten about it. It was holding at about 60% cpu the last couple of days and I couldn’t figure it out until I searched the forums for this issue. Solved it for me and I’ll be trying other email clients anyway.
Not to mention, most of these trucks are very standardized in their dimensions and parts already. This is probably the biggest thing that will hurt small vehicles is picking a subset of standardized dimensions that will fit multiple models.