As I stated above: “Please note that, for S2259 to show up in-IDE you need to use SonarQube IDE in connected mode to SonarQube Cloud or SonarQube Server Developer Edition or above”.
S2259 is one of the advanced bug detection rules that are not offered in the SSAL licensed plugins since version 10.2 (released in November 2024).
You can still benefit from them for free when using the SonarQube Cloud Free plan (for public projects) and in-IDE using SonarQube for IDE in connected mode.
Denis