When I have ReSharper enabled, double clicking on a word doesn't always select the text ( double click then <ctrl>+c is a common part of my workflow). I can usually reproduce this behavior with the following steps.
1. Enable ReSharper, restart VS.
2. Open a .cs file and click once in a variable name to place cursor.
3. Double click in the same place.
When resharper is disabled, the word is selected as expected after a double-click action. When resharper is enabled, nothing happens.
c# VS 2022 community, resharper v 222.0.20220808