Any mouse button can be used to interact with entries in the world, server, and language selection screens

When interacting with entries in certain selection list screens, side mouse buttons (Mouse 2, 3, 4, and 5) can trigger selection and activation actions despite not being bound to any in-game functions.

Affected screens:

• Single-player world selection (Singleplayer → select a world): Side mouse buttons can select a world entry. When the entry is already selected, clicking it again with a side mouse button will load the world.

• Multiplayer server selection (Multiplayer → select a server): Side mouse buttons can connect to a listed server. For servers shown in the online server list, clicking the server icon area with any side mouse button immediately initiates a connection without requiring the entry to be pre-selected.

• Language selection (Options → Language): Side mouse buttons can select a language entry. When the entry is already selected, clicking it again with a side mouse button will apply the language change and close the screen.

Steps to reproduce (world selection example):

1. Open the singleplayer world selection screen

2. Left-click a world entry to select it (it becomes highlighted)

3. Click the same highlighted entry again using Mouse 2, 3, 4, or 5

4. The world begins loading

Expected behaviour:
Only Mouse 1 (left click) should be able to interact with list entries.

Actual behaviour:
Mouse 2, 3, 4, and 5 can select and activate list entries, triggering world loading, server connections, or language changes.

See also: MC-297502 (same root cause — side mouse buttons bypass button validation in specific GUI click handlers)