Well, as the title says... Sometimes or after some time, the mouse cursor disappears, making it nearly impossible to do anything. Most of those times i just have to Alt+Tab and stop Rfactor 2 from the Windows Task Manager (Windows 7)
I had this problem yesterday and neither Del nor backspace restored the cursor. What made it slightly worse (with triples) was that under the old UI, you used to get an audible ‘blip’ when your (invisible) cursor passed over an rf2 button - so you could at least wave the mouse around until you started to hear the blips and then try and localise the position by looking out for button highlights... No idea why the audible feedback has been (totally) removed - annoying for some, no doubt, but in a UI where links/buttons are not always obvious....?
