Hello, I'm Mike and I recently installed Linux Mint Debian Edition 6 Beta2 on a 2009 iMac10 with an Intel Duo E7600 3.059GHz CPU. Before that, I installed Linux Mint 21.3. I was also experiencing the same problem with loosing the desktop cursor after about 20 minutes of use. After reading many, many posts of possible options to correct this problem, I ended up doing the following and so far it has been working. In the settings menu, I disabled the touch pad settings. Since this is a desktop, why would it need to be enabled. Next, I totally removed 2 apps from the Synaptic Package Manager, 1. intel-microcode i.e. Processor microcode firmware for Intel CPUs. 2. iucode-tool i.e. Intel Processor microcode tool. Once this was done, I rebooted. I can't tell you why being a newbie with iMacs and Linux but, it works. I hope it will work for you. Mike