New install of 2019, did not import user files. First saw this when editing a file started in 2018, but after only a few operations my view looks like a 1980 video game. once it happens it pops in and out of this state as I move the cursor. The file in the screenshot is brand new. Started inserting truss and on the last stick it did this. If I pan and zoom there is a ghost image retained of the moment that the glitch occurred. That's what the white grid to the left is. The purple is the current page outline. If I go into a 3d view, it shifts to green, but otherwise remains the same, glitching in and out as I move the cursor.