Texture picker sometimes does not show "Multiple textures" when multi-selecting materials.

Environment

Second Life Release 7.1.15.15352812358 (64bit)
Release Notes

You are at 66.4, 40.3, 39.3 in Danger! Danger! located at simhost-0f66654f1bf388d1c.agni
SLURL: http://maps.secondlife.com/secondlife/Danger%21%20Danger%21/66/40/39
(global coordinates 261,186.0, 249,640.0, 39.3)
Second Life Server 2025-04-24.14648572313
Release Notes

CPU: AMD Ryzen 9 5980HX with Radeon Graphics (3293.72 MHz)
Memory: 15775 MB
OS Version: Microsoft Windows 11 64-bit (Build 22631.5335)
Graphics Card Vendor: ATI Technologies Inc.
Graphics Card: AMD Radeon RX 6800M

Windows Graphics Driver Version: 30.0.15020.1001
OpenGL Version: 4.6.14800 Core Profile Context 21.50.20.01 30.0.15020.1001

Window size: 1867x1388
Font Size Adjustment: 96pt
UI Scaling: 1
Draw distance: 128m
Bandwidth: 3000kbit/s
LOD factor: 1.75
Render quality: 5
Texture memory: 11474MB
Disk cache: Max size 1638.4 MB (42.9% used)

J2C Decoder Version: KDU v7.10.4
Audio Driver Version: OpenAL, version 1.1 ALSOFT 1.24.2 / OpenAL Community / OpenAL Soft: OpenAL Soft
Dullahan: 1.14.0.202408091639
CEF: 118.4.1+g3dd6078+chromium-118.0.5993.54
Chromium: 118.0.5993.54
LibVLC Version: 3.0.21
Voice Server Version: Vivox 4.10.0000.32327.5fc3fe7c.5942f08

Packets Lost: 3/20,073 (0.0%)
June 05 2025 18:16:17

Description

Texture picker sometimes does not show "Multiple textures" when multi-selecting materials on an object if one of the materials exists in your inventory.

Reproduction steps

1. Get the test object "viewer#4223 v.2" from http://maps.secondlife.com/secondlife/Danger!%20Danger!/73/79/39
2. Edit the box and select the Texture tab.
3. Choose "Select Face" on the edit dialog
4. Select the side with the blue and yellow circles.
5. Click the material swatch to open the Texture picker.
6. Shift-click the top face.
7. Observe that the swatch in the Edit tool says "Multiple", and the swatch in the Texture picker says "Multiple textures"
8. Drag a material from your inventory onto the top face of the box.
9. Again edit the side with the blue and yellow circles, click the material swatch to open the Texture picker, shift-click the top face.

Observed: The swatch in the Edit tool says "Multiple", but the swatch in the Texture picker does not say "Multiple textures"

Video: https://github.com/user-attachments/assets/e3bd7ac7-5fea-43e8-b768-4bd834dc309f

Expected: The texture picker should say "Multiple textures" whenever 2 or more different materials are selected on an object.

Note: This bug was also seen in 7.1.10.10800445603 - DeltaFPS, so it's not a recent regression.

Reproduce the issue with the “viewer#4223 v.2” object, then trace the Texture tab, material swatch, and Texture picker handling for multi-selected faces. The fix is complete when the picker displays “Multiple textures” whenever two or more different materials are selected, including when one material exists in inventory.