Windows 10 RDP behaviour seems to have changed post April update. Same hardware, same mouse, same OS, same everything.
I'm connected to a remote session (Windows Server 2012 R2) and am experiencing this in Notepad, Notepad++, Textpad and Visual Studio Code:
Typing Shift+'and then u does not print "u and instead prints Ü
For example: to type
I type $ s q l = (shift+') u p d a t e
To get around this new and annoying issue I am typing shift+' shift+' (twice) to print "" and then moving the cursor back inside the quotes to type update.