I wonder if there is a way to make ubuntu-frame ignoring the long touch. I simply want to manage any touch event in the same way, without distinguishing if it is a short or long touch of the display.
The short answer is no: Ubuntu Frame simply passes the touch-down & touch-up events to the app whenever they occur.
It is the app (or the framework it is built with) that decides how to handle a “long touch”.
Fair enough. So it means I should have a look at the browser on top of ubuntu-frame? I am currently using wpe-webkit-mir-kiosk snap.
Thank you @alan_g. I figured it out looking into the code of the web app that is running on top of wpe-webkit-mir-kiosk. Actually there are some old fashion parts that are not compatible with touch gestures. Performing tests using a much reliable webpage (that I wrote myself ), it works like a charm.