Visual Studio Code gives me errors when using "Rename symbol"

I'm using Visual Studio Code to edit my C# files. I have a triangles variable that I use several times with no problem:

Whenever I rename it with "Rename Symbol", my VS Code editor gives me an error for each instance of that variable. Even though they've all been renamed to tris, now intellisense t$$anonymous$$nks it's called triew, further down, it t$$anonymous$$nks it's tri, and it t$$anonymous$$nks the + symbol is an = symbol. Everyt$$anonymous$$ng goes bonkers. I overlayed the errors in a single image below:

I try cutting & pasting the lines, or adding spaces, but the editor seems to remember the errors. I have to close Visual Studio Code and reopen it for it to re-evaluate the file and realize that it didn't have a problem all along. Is it a problem with OmniSharp? I uninstalled VSCode and reinstalled it, to no avail. I'm using VSCode 1.50.1 with Unity 2020.1.8f1