Instructions: text select/highlight by dragging with the mouse any part of the text in the orange-bordered input.
Actual results in Firefox 52.9.0 ESR buildID=20180626223325: APPLICATION CRASH
Actual results in Firefox 63.0a1 buildID=20180721220720: the whole text in the orange-bordered input disappears.
Expected results: the highlighted text replaces the whole text in the orange-bordered input.
Chromium 67.0.3396.87 and Opera 56.0.3013.0 (Edition developer; Chrome/69.0.3472.3) achieve expected results.