I am using the following
side widow shades when waiting at a supercharger on a sunny day.
Note: Because of the Tesla frame-less side windows, it is not possible to attach the shade to the window.
I have a Model 3, so I didn't tried the Model Y version, but
the shades that I have fit perfectly when installed from inside the car.
The shades stay in place even if you open the windows with the door closed, however you have to be careful
when you open the door because the shades don't stay attached to the door and could drop on the floor.
I tried adding a little clip on the top to keep the sunshade attached to the window when opening the door,
but when you open the door the window goes down a little bit and then the clip slides away.
The best solution to keep the shades attached to the windows is to put a little rope horizontally all around the window.
This is not a perfect solution, but I find it helpful, you can even drive and the rope outside will not get affected by the wind.
But every time you open the door the rope move a little bit, so after a while you need to readjust the rope.
Those side window shades are easy to install and this is a simpler solution than tinting your windows.