[Bug]: Selection doesn't copy to X selection (clipboard)

[UnderSampled]

Is there an existing issue for this?

• [X] I have searched the existing issues

OS/Web Information

• Web Browser: Firefox 91.11.0esr
• Local OS: Debian 11.4 (bullseye) with KDE through Xorg
• Remote OS: (same)
• Remote Architecture: amd64
• code-server --version: 4.5.1 97d170331b51ee75c8e4bbdab23c755e3eeaaa8c with Code 1.68.1

Steps to Reproduce

1. Open a document or terminal in code-server in a browser through the X Window system
2. Select some text
3. Use middle-click to paste

Expected

In X windowing environments, middle clicking should paste the text that was selected at the location under the mouse cursor.

Actual

Text is pasted upon middle click, however it is not the text that was selected within the code-server UI. Instead, it pastes the most recently selected text from outside the page, including from other tabs within the same browser.

Logs

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Screenshot/Video

No response