Disappearing cursor

Could it possibly be a Finder-related issue? Have you tried relaunching the Finder by holding down the Option key, and then right-clicking the Finder icon in your Dock, and then selecting "relaunch"? What about deleting ~/Library/Preferences/com.apple.finder.plist and rebooting your Mac so that it can create a new plist file?

FWIW, the cursor periodically will disappear for no apparent reason. You also can bring it back by right/control clicking on the Desktop. Sometimes.

¡Excelente, mi amigo! Glad you got it worked out! Good going! In this case, which of the two options I suggested worked for you? Or did it require doing both?

Great! Glad to hear it. That second approach replaces your Finder prefs file with a new, virgin copy of the same.