README: update info about HLS

README.md

@@ -427,10 +427,15 @@ Maybe you need to change the port to 5433 for database connection in your gargan
 If you want to use `haskell-language-server` for GHC 9.4.7, install it
 with `ghcup`:
 ```shell
-ghcup compile hls --version 2.7.0.0 --ghc 9.4.7
+ghcup compile hls --version 2.11.0.0 --ghc 9.6.6 --cabal-update
 ```
 https://haskell-language-server.readthedocs.io/en/latest/installation.html
 
+*NOTE* Sometimes it helps to remove `$HOME/.cache/hie-bios` if you
+experience strange errors like
+```
+fatal: Could not parse object '316d48b6a89593faaf1f2102e9714cea7e416e56'.
+```
 
 ## Running the tests <a name="running-tests"></a>