Chrissy LeMaire has an extension which allows for quick searches of highlighted text on a few sites:
We recently released a VS Code extension that lets you highlight terms and search dbatools.io, Microsoft Docs, Google, StackOverflow, DuckDuckGo or Technet or Thwack right from your code! It’s called dbatools simple search and you can find it in the Extension Marketplace.
I’ve also confirmed that it does work with Azure Data Studio; you just need to download the vsix extension from the Extension Marketplace and install and get context menu search support.