I am able to hide all of my stereo tracks in the project window, but I am unable to hide the midi tracks in my mixconsole. I am new to Cubase 9.5 and would appreciate any help. I’ve tried clicking and unclicking the dots and arrows in the track visibility and zone visibility tabs in the right zone. I’ve also tried using the filter track types and turning off and on the syncing the track visibility button. I’ve consulted the manual and I watched a plethora of YouTube videos with no clear answer. Any help would be great.
I believe this thread to contain a workaround for your issue:
We have to be patient until a fix is available. 
Thank you Hurmpie. Also, thank you Panther.
was looking for that too. thx