Middle click + drag doesn't work correctly if middle click is inside preview iframe

@jessebaker provided feedback — do you think you could address that, @balintbrews? 😊

@balintbrews: FYI: @jessebaker pushed a commit and commented on the MR 😊 (Just in case you missed that.)

New issue has been created for that remaining bug: 🐛 Middle click + drag and moving fast with the mouse miscalculates canvas scroll position Active .

I added the 3458535-test-gitlab-ci branch to help narrow down the Cypress tests CI job dying before Cypress can even begin. Turns out I didn't have to do anyting other than possibly getting it current with 0.x - if it's easiest to continue work on that branch that's fine - the only difference is it is current.

Tagging with needs tests. This should be testable since cypress-real-events supports middle-clicks.

balintbrews → closed merge request !79

… but I think we'll still want a second MR for this issue, to add tests, as requested by @bnjmnm in #13? 😊😇