Broken/incorrect observer mode in dead spec

[Rainyan]

Build Info

v10.0-prealpha

Description

Sometimes, when spectating players whilst yourself dead, in the first person mode, their weapon viewmodel is not visible. It also seems some other props in the vicinity sometimes get culled away in strange ways, as if you were in a different PVS leaf (spotted occurring in close corridor hallways etc). This might be an issue with the incorrect observer mode enum being set, but I'm unsure.

It doesn't seem to happen consistently, sometimes it works, but other times not. Possibly related to the auto-obstarget choosing behaviour when you (your your current observer target) dies.

To Reproduce

• Have some players/bots in both teams
• Join a team yourself
• Play the CTG game mode (no respawns)
• Wait for the round to start
• Die
• Start spectating your remaining teammates in first person view

Expected behavior

Able to spectate in the first-person view correctly, and the spectated player's weapon viewmodel is visible.

Actual behavior

The spectated player's viewmodel is invisible.

Operating System

• Windows
• Linux

Version/Distro

Linux Mint 21.3 Cinnamon

Machine's CPU

AMD Ryzen 5 7600

Machine's GPU

AMD RX 580

GPU's driver

Mesa 23.2.1-1ubuntu3.1~22.04.2

Build's compiler

No response

Additional context and Screenshots

Note how the viewmodel breaks when auto-switching to the new spectating target when your previous spec target dies:

vmbug.webm

[Rainyan]

Similar issue, but unknown if related: #803