Hello there 
i am still using my old 9,1 iMac (early 2009) with Catalina 10.15.5 (Dosdude) .
After upgrading with ssd and bt 4.0 and ac wifi this machine is still fast enough for daily use.
But: when I plug in a BENQ G2420HBL Catalina logs me out to the login screen. The BENQ screen shows the Desktop background pic. I played with all kinds of cables and adapters but no succeed. With Mojave it works as it supposed to be. And on my iMac late 2015 the BENQ Monitor works with any cable or adapter.
I know that in Catalina Apple changed it for more security and I read about screen recording permission in the preferences. But I couldn't get anything to work.
Its working in safe mode. But when I reboot into normal mode, the same game again. Only when I unplug the BENQ Screen again, Catalina lets me logging in.
Does it has to do with the Display Port version of the iMac and the Benq Screen (the iMac has DP 1.1 and the BENQ has 1.1 or 1.2) ? Is there any solution software wise or is the BENQ just not compatible for Catalina? Did Apple ditch some compatibility for more security?
Thank you for your time
i am still using my old 9,1 iMac (early 2009) with Catalina 10.15.5 (Dosdude) .
After upgrading with ssd and bt 4.0 and ac wifi this machine is still fast enough for daily use.
But: when I plug in a BENQ G2420HBL Catalina logs me out to the login screen. The BENQ screen shows the Desktop background pic. I played with all kinds of cables and adapters but no succeed. With Mojave it works as it supposed to be. And on my iMac late 2015 the BENQ Monitor works with any cable or adapter.
I know that in Catalina Apple changed it for more security and I read about screen recording permission in the preferences. But I couldn't get anything to work.
Its working in safe mode. But when I reboot into normal mode, the same game again. Only when I unplug the BENQ Screen again, Catalina lets me logging in.
Does it has to do with the Display Port version of the iMac and the Benq Screen (the iMac has DP 1.1 and the BENQ has 1.1 or 1.2) ? Is there any solution software wise or is the BENQ just not compatible for Catalina? Did Apple ditch some compatibility for more security?
Thank you for your time
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