Flatpak version of Waterfox when pinned to dock spawns new instance rather than opening as expected on Pop!_OS 24.04

[TundraFox907]

What happened?

Steps to reproduce:

• Install Pop!_OS 24.04 with the Cosmic DE
• Install the Flatpak version of Waterfox (since no apt repo seems to exist)
• Pin Waterfox to the dock/panel
• Click the icon to launch the app
• A second instance of the app will spawn without an icon. Interacting with the icon version such as clicking it to open a minimized window will spawn a new instance of Waterfox rather than the expected behavior.
• This behavior is consistent and persists through uninstalling/reinstalling Waterfox, reboots, etc.
• Other flatpak apps do not behave in this manner under Cosmic, making me think this is a WF issue, not a Cosmic issue.
• This behavior does not occur in Pop!_OS 22.04.
• This behavior is not reproducible on either the deb or flatpak versions of Firefox.
• Pinning this icon-less instance of Waterfox to the dock/panel causes it to disappear and alt-tab is the only sign that it is still running.

Reproducible?

• I have checked that this issue cannot be reproduced on Mozilla Firefox.

Version

G6

What platform are you seeing the problem on?

Linux

Relevant log output