Tested versions

• Reproducible in: v4.6.dev1.official [8d8041b], v4.6.dev3.official [9d84f3d]
• Not reproducible in: v4.5.1.stable.official [f62fdbd]

System information

Godot v4.6.dev3 - Arch Linux #1 ZEN SMP PREEMPT_DYNAMIC Sun, 02 Nov 2025 17:27:04 +0000 on Wayland - X11 display driver, Multi-window, 2 monitors - Vulkan (Forward+) - dedicated AMD Radeon RX 570 Series (RADV POLARIS10) - AMD Ryzen 7 5700X 8-Core Processor (16 threads) - 31.24 GiB memory

Issue description

When using reflection probes with update modes of both Once and Always in the same tree, the game starts lagging and VRAM usage maxes out (at least on my 8GB graphics card). Sometimes, the probes also start flickering in and out.

Steps to reproduce

POSSIBLE FLASHING LIGHTS WARNING ON STEPS 5 AND 6

1. Start the MRP in Godot v4.5.1
2. Press Space to toggle the realtime probe attached to the moving sphere with update mode set to Always
3. Press keys 1-4 to toggle the probes in according rooms with update modes set to Once
4. There should not be any unusual performance problems or unexpected jumps in VRAM usage, all probes will work
5. Start the MRP in Godot v4.6 and perform the same actions
6. Performance will start dropping when there are probes with both Once and Always update modes active, VRAM usage will jump up to max, and static reflection probes will either go away or start flickering (hence the flashing lights warning)
7. Set the static reflection probes' update modes to Always and start the MRP again
8. Problem goes away

Minimal reproduction project (MRP)

reflection_probe_always_update_memory_leak_mrp_2025-11-08_21-19-34.zip