TIFF viewer shows images 4x the size, padded with zeros

[kostrykin]

Describe the bug
TIFF viewer shows images 4x the size, padded with zeros.

Galaxy Version and/or server at which you observed the bug
Galaxy Version: {"version_major":"25.1","version_minor":"2.dev0"} (usegalaxy.eu)

Browser and Operating System
Operating System: macOS
Browser: Firefox

To Reproduce
Steps to reproduce the behavior:

1. Go to https://usegalaxy.eu/u/kostrykin/h/test-2026-03-11-b
2. Click on the "view" icon (eye) next to Dataset 33
3. See screenshot below how the TIFF viewer displays the image

Expected behavior
The image should look like in ImageJ for example:

This is the same image as below.

Screenshots

Additional context
Maybe related to #22068?

[davelopez]

Hi @kostrykin!
That is very strange! When I click the view icon in the image link you posted, I can see the image without that extra padding 🤔

[kostrykin]

@davelopez I just tested it again and it seems it only happens in Firefox, not in Safari. Don't know about Chrome.

[kostrykin]

And yes after further testing I think this is related to #22068, because clicking the zoom buttons actually zooms the center of the padded image. It's just that in Safari the padding is white (and hence not visible), and in Firefox it is black.

[davelopez]

Hmm, we need to investigate a bit more. I just tried in Firefox, and it still works as expected:

What happens when you click "Fit to screen"?

Also, what do you get when checking the image info for ImageWidth and ImageLength? I get 1024x1024, which I assume is correct.

[kostrykin]

The viewport returns to the original when I click "Fit to screen".

Image width and height are reported correctly as 1024x1024.

out.mp4

[kostrykin]

I just tested it on more computers, overall, the situation is as follows:

• macOS 15.6 + Firefox 148.0.2 aarch64: error confirmed 💥
• macOS 15.6.1 + Firefox 148.0.2 aarch64: error confirmed 💥
• macOS 26.3 + Helium 0.10.2.1 based on Chromium 146.0.7680.71: error confirmed 💥
• macOS 26.3 + Firefox 146.0.1 aarch64: error confirmed 💥
• Ubuntu 24.04 + Firefox 147.0.4 64-bit: no error 🟢
• Ubuntu Ubuntu 22.04 + Firefox 148.0.2 64-bit: no error 🟢
• Windows 10 + Firefox 147.0.4 64-bit: no error 🟢
• Windows 10 + Firefox 148.0.2 64-bit: no error 🟢

Seems to be a macOS or aarch64-only issue?

What is strange is that the error concerns both Firefox and Helium/Chromium, which AFAIK use different engines.

[davelopez]

Thanks so much for the testing!
Ugh, if it only affects macOS I don't know how we can fix that 😞. Unfortunately, I don't have a macOS available right now to reproduce and to try to figure out a solution.

I'll try to fix #22068, but I don't think that one is related to this because I can reproduce the Zoom issue.

[kostrykin]

Some more debugging info…

On systems where the error is observed, I see the following HTML in the browser console:

<canvas style="user-select: none; touch-action: none; transform-origin: 50% 50% 0px; transition: none; transform: scale(0.437988) translate(28.5396px, -535.973px); width: 1024px; height: 1024px;" width="2048" height="2048"></canvas>

On system where it is not observed, the HTML is:

<canvas style="user-select: none; touch-action: none; transform-origin: 50% 50% 0px; transition: none; transform: scale(0.630859) translate(211.616px, -313.858px); width: 1024px; height: 1024px;" width="1024" height="1024"></canvas>

The difference is width="2048" height="2048" vs width="1024" height="1024".

[davelopez]

I asked Copilot for some insight, and it is likely caused by the retina resolution and how it is handled in the TIFF viewer. There is a PR galaxyproject/galaxy-visualizations#153 that removes the DPR handling. I cannot try it myself, but if you (or any macOS user) want, you can check out that branch, cd into the packages/tiffviewer/ directory, and then run the following (replacing with your corresponding values):

GALAXY_ROOT=http://localhost:8080 GALAXY_KEY=<GALAXY_API_KEY> GALAXY_DATASET_ID=<DATASET_ID> GALAXY_HISTORY_ID=<HISTORY_ID> npm run dev

I hope that helps!

[davelopez]

This should be fixed in galaxyproject/galaxy-visualizations#153, but the 0.0.4 version of the https://www.npmjs.com/package/@galaxyproject/tiffviewer npm package needs to be published. Maybe someone with publishing access, @guerler or @dannon can run the publishing step? Then I can bump the version in https://github.com/galaxyproject/galaxy/blob/dev/client/visualizations.yml#L113