As a matter of interest Ms Charli, I have just purchased a TECKNET Bluetooth Mouse and Arteck Bluetooth Keyboard for working within Dex as my desktop replacement BUT came across the same issue as yourself... I did use the Ctrl+C and Ctrl+V and this worked well, And I have now tried left clicking my proposed selection, dragging it to the right which does select it but I do not get any options on Right Clicking the mouse??
As you have many more months of experience of these issues maybe you can tell me - or give me some advice of the best mouse practices you have found on the Tab S4 in Dex with mouse use.
I have also found that when using the Google Chrome App ( which is my preferred Browser across my many devices) I am having issues when I try to left click on the Option to turn on Desktop View. When I left click the Burger Bar (top Right) it appears for a few seconds and then as I mouse the mouse down to select something the menu disappears - which is extremely annoying - to the point of nearly swearing at the device (okay sometimes I do!) ... have you or anyone else come across this issue?
Thanks in advance for any advice or suggestions given.
Enjoy your week!
Fanflame