Scrollbar annotations on iPad

I’m trying to get scrollbar annotations to show on an iPad CodeMirror view, using addon/scroll/annotatescrollbar.js, CodeMirror release 5.43.0. Out of the box, nothing shows up. The reason is there’s a test on line 88 of annotatescrollbar.js involving cm.display.barWidth, and nothing happens if that is zero. Which at the moment it is, for me at least, on an iPad. If I experimentally add a line just before that right in annotatescrollbars.js, “cm.display.barWidth = 17;” then the scrollbar annotation markers appear and everything is fine.

Would anyone know a legitimate way to persuade scrollbar annotations to appear on an iPad, or force cm.display.barWidth to be 17 just for the iPad?