Look into cl-opengl's multi context issues

[cbaggers]

https://github.com/3b/cl-opengl/issues/10

23:50 <|3b|> borodust, Baggers: cl-opengl technically doesn't support multiple contexts, so be careful how you use it with them (specifically if you use immediate mode you need to add some code to make the automatic error checking work or disable it, and on windows it won't work with context from different drivers) 23:51 <|3b|> (and may even break on contexts from same driver, but haven't heard of that being a problem in practice)

[cbaggers]

https://github.com/3b/cl-opengl/issues/78