Earlier quoted context omitted.
* Download Ublock zip * Enable Developer Options * Add Ublock package zip * Enable in Incognito as well TL;DR: Them removing it would be a dick move, but not end of the world. We can still install any packages we want.
I can say from experience that there are plugins which Chrome actively removes even if installed this way.
Have you tried Packing them? I have yet to experience this.