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Could you please check if the resolution of your screen if high.Please lower down the resolution of your screen and then try to record. If that still doesn't work then please create a new user account with admin rights and then try to record or edit.
Please let me know if that works.
Thanks very much, Rajeev.
This does work, which is great, although a shame that I'll have to change every time I want to record something and won't be able to take advantage of the better resolution.
Do you know if there is any chance of an upgrade or patch to fix this in the near future?