COGLayer/MosaicLayer render nothing in Firefox and non-Google Chromium builds, no error thrown

## Environment

- `@developmentseed/deck.gl-geotiff`: 0.7.0
- `@deck.gl/core`, `@deck.gl/mapbox`, `@deck.gl/layers`, `@deck.gl/geo-layers`, `@deck.gl/mesh-layers`: 9.4.0
- `@luma.gl/core`, `@luma.gl/shadertools`: 9.4.0
- `maplibre-gl`: 6.7.0, integrated via `@deck.gl/mapbox`'s `MapboxOverlay` (`interleaved: false`)
- OS: Windows 11 24H2

## Observed behavior matrix

Same page, same COG source, same machine:

| Browser | Renders? |
|---|---|
| Firefox (current) | ❌ no imagery, no error |
| Chromium 131.0.6778.265 (unbranded open-source build, not Google Chrome) — normal and Incognito | ❌ no imagery, no error |
| Microsoft Edge (current) | ✅ |
| Playwright's Chrome-for-Testing (headless and headed) | ✅ |

`chrome://gpu` on the failing Chromium build reports WebGL2 as hardware-accelerated, so it's not a coarse "no GPU acceleration" issue.

## Steps to reproduce

1. Create a MapLibre GL JS map, add a `MapboxOverlay` (`interleaved: false`) via `@deck.gl/mapbox`.
2. Add a `COGLayer` (or `MosaicLayer` wrapping one) pointed at any COG.
3. Open in Firefox, or in an open-source (non-Google-branded) Chromium build.

## Expected

The COG renders, as it does in Edge/Chrome.

## Actual

Nothing renders. No JS exception, no `pageerror`, no fatal console error in either failing browser. The only console output is:

```
luma.gl: WebGL uniform block reflection failed for "phongMaterialUniforms"; using supplied std140 metadata. ...
luma.gl: WebGL uniform block reflection failed for "lightingUniforms"; using supplied std140 metadata. ...
luma.gl: Binding sampler not set: Not found in shader layout.
```

Note these same warnings also appear in the *working* browsers (Edge, Chrome-for-Testing), so they may be unrelated noise rather than the actual cause — flagging them only because they're the only signal present.

## Notes

- We did not get further than this — no fatal error to trace, so we couldn't pin down the exact failing call.
- Ruled out: extensions/privacy tools (reproduced in Firefox in a fresh profile-equivalent test and in Chromium's Incognito mode), coarse WebGL2/hardware-acceleration availability (`chrome://gpu` confirms it's on).

Start by reproducing the issue with COGLayer or MosaicLayer through @deck.gl/mapbox's MapboxOverlay (interleaved: false) in Firefox and the non-Google Chromium build, comparing Edge and Chrome-for-Testing. Trace the WebGL2 rendering path around the reported uniform-block and sampler warnings, then verify that a COG renders in both failing browsers.

Written by the indexing model from the issue text.