Steps: - create an iframe without src - create click event listener on any other element - set iframe src to on click to some url that supports "go to application" e.g. YouTube embed url Expected: Iframe shows youtube video on element click Actual: Firefox asks to open a new tab or open an app, and never shows this in iframe Fix for developers: Recreate the iframe with the src It only works on ff android, we spent literally hours to catch this bug