Describe the bug
Using the latest STS4 CI build for Eclipse 2021-09, it looks like the symbols dialog doesn't work anymore. Cmd-6 doesn't show up any symbols popup. The same seems to happen for the Symbols view, it remains empty.

The console output from the language server seems to be totally fine and looks like the language server is doing the usual job. But the symbols features on the UI don't work anymore.

To Reproduce
Fresh install of STS4 from CI builds on Eclipse 2021-09, fresh workspace, import Rest Service guide project (complete version only), open editor, press CMd-6 => nothing happens. Open View -> Symbols View => remains empty.