[eduren]

So with the comparisons at the end of the article, does this mean that there were a lot of edge cases where the theming wasn't being correctly applied prior to 1.9? Were there themes that incorporated less stylistic choices because of the limitations?

[alexdima]

Yes, those comparisons at the end show differences in rendering caused by the "approximations" used prior to VS Code 1.9. They were all caused by the difference between the ranking rules of CSS selectors and the ranking rules of TM scope selectors