WebUI: append port to session cookie name

[dyseg]

Prevents overwriting the shared cookie between qBt sessions on the same host.
Separated from #21618. Original topic: #20873 (comment)

[glassez]

The issue of multiple qBittorrent instances under the same host was already fixed by implementing suggestion of allowing you to set custom cookie name.
Original Issue is #18329. Fixed by #18384.

[dyseg]

In this case from my side this PR can be closed.

[Piccirello]

It would be really nice to fix the multi-instance scenario for users without requiring them to manually configure a custom cookie name. I suspect most users are not aware of this footgun, and so having a comprehensive fix will also prevent these users from opening GitHub issues unnecessarily.

[Piccirello]

An alternative would be to come up with a unique cookie name on startup.

[glassez]

IMO, the current method looks better, since it still identifies the cookie name with a specific qBittorrent instance, so that some client with a smarter implementation than browsers (which is why the problem is) could even send it to a specific instance and not to everyone on the same host.

[glassez]

It would be really nice to fix the multi-instance scenario for users without requiring them to manually configure a custom cookie name. I suspect most users are not aware of this footgun, and so having a comprehensive fix will also prevent these users from opening GitHub issues unnecessarily.

It's reasonable.
But shouldn't it then completely replace the current solution with a manually set name? It hardly makes much sense to have both of them at the same time.

[Piccirello]

It's reasonable. But shouldn't it then completely replace the current solution with a manually set name? It hardly makes much sense to have both of them at the same time.

Yes, I think having this would eliminate the need for setting a custom cookie name.