Gallery: zoom small images beyond display resoulution

OK, this is my first time working with github (other than doing "git clone http...") I never did fork a project.

I wrote a patch for the gallery to enable more zooming - please also see here:
https://together.jolla.com/question/4416/gallery-zoom-beyond-display-resolution/#56483

Is this the right place and way to do it ? I mean forking sailfishos-patches-advanced and pull-request?

Greetings

Darvari