Does the "Rename Symbol" feature work across files, when editing JavaScript? Currently it's only working within the current file being edited. I seem to recall it working across files, though. It would open all the files that it had made changes to. It's no longer doing that, though.
Am I remembering incorrectly or does it work this way?
The feature Rename Symbol only works for the current file. But there is another feature, which fits your description: Replace in Files (Menu Bar: Edit > Replace in Files).
From Visual Studio Code User Guide:
You can also Search and Replace across files. Expand the Search widget to display the Replace text box.
When you type text into the Replace text box, you will see a diff display of the pending changes. You can replace across all files from the Replace text box, replace all in one file or replace a single change.
For a quick use you can select a word in your source and hit Ctrl+Shift+H.