Missing quotes around attributes selector

This fixes #9125 as this was causing issues with some specific ids only composed of HTML encoded characters (like russian language headers)

Author: cderv

news/changelog-1.5.md

@@ -8,6 +8,7 @@ All changes included in 1.5:
 - ([#8862](https://github.com/quarto-dev/quarto-cli/issues/8862)): Properly deal with an `aside` within a definition list.
 - ([#8990](https://github.com/quarto-dev/quarto-cli/issues/8990)): Copy button now works for embedded code source in modal window when optin-in `code-tools` feature.
 - ([#9076](https://github.com/quarto-dev/quarto-cli/issues/9076)): Fix issue with `layout-ncol` and `column` settings in executable code cells.
+- ([#9125](https://github.com/quarto-dev/quarto-cli/issues/9125)): Fix issue in browser console with TOC selection when the document is using ids for headers with specific characters (e.g russian language headers).
 
 ## PDF Format
 

src/resources/formats/html/quarto.js

@@ -94,7 +94,7 @@ window.document.addEventListener("DOMContentLoaded", function (_event) {
       if (link.href.indexOf("#") !== -1) {
         const anchor = link.href.split("#")[1];
         const heading = window.document.querySelector(
-          `[data-anchor-id=${anchor}]`
+          `[data-anchor-id="${anchor}"]`
         );
         if (heading) {
           // Add the class