Rollup merge of #66430 - dns2utf8:fix_code_selection_click_handler, r=GuillaumeGomez
Rollup merge of #66430 - dns2utf8:fix_code_selection_click_handler, r=GuillaumeGomez

[doc] Fix the source code highlighting on source comments

The code would always forget the previous selection.

r? @GuillaumeGomez

graydon/rust,graydon/rust,aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust