It's been sitting around a long time and I don't remember where I got it from. Thanks for the link though.
By the way, in Chrome on Android, you can't execute bookmarklets from the bookmark menu. You need to give the bookmarklet a name. Say "Upsize". Then when you are on the page where you want to increase the font size, type "up" in the url bar and click on "Upsize" in the suggestions. Might be the same in Firefox?
Firefox used so be super useful on Android, but since its redesign almost all its customizability has been gone. So sad.
In fact, it works both ways:
I can click on "bookmarks" and then on the bookmarklet, and it gets executed on the current page.
I can also start typing the bookmarklets name and then click on it in the suggestions. It then also gets executed on the current page.