I must say I'm not convinced about the browser/OS settings thing. I don't have this issue with any other program (eg. CMD+scroll gesture does nothing in Chrome, or even in the Construct start page - only in the editor tabs). It seems to be a 'Construct zoom', not a 'browser zoom' (I can trigger a browser zoom separately, anyway).
I must admit I'm not super familiar with Mac. On windows, ctrl+mouse wheel is the shortcut, in any browser, to control its zooming feature/make the text font bigger in any web page.
Chrome on Mac is actually the Safari browser, so consider checking Sfari's settings.
It is "normal" that ctrl(cmd)+mousewheel does zoom in the event sheets, it is treated like any web page in which you can zoom/make the text font bigger.
I've tried a few things, including disabling trackpad zoom in System Preferences and disabling Chrome zooming with extensions, but the event-sheet zoom problem still occurs. No other web pages zoom in/out when holding command and moving two fingers on the trackpad - it certainly feels like a Construct zoom feature, so hopefully it can be an option we can disable.
Maybe that is the case.
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