Steps to replicate the issue (include links if applicable):

• Click on any image on a MediaWiki instance that has the MediaViewer installed.

What happens?:

"There seems to be a technical issue. You can retry or report the issue if it persists."

What should have happened instead?:

Should open up the picture in the viewer.

Workaround

Until this is remedied by the code maintainers, the easiest workaround is:

1. Edit:

extensions/MultimediaViewer/resources/mmv/provider/mmv.provider.Image.js

2. Go to the line containing the function

imagePreloadingSupported() {

3. Comment out the following line (using the forwardslashes -- // ):

return window.XMLHttpRequest !== undefined && 'withCredentials' in new XMLHttpRequest();

4. Add on a new line underneath it (before the } ) to read:

return false;
That should work around the issue.

Kindly note that every time you update MediaWiki (and also update the extensions) you will likely need to change this as it over-writes previous versions. (This is also an issue with the 1.44 that was released on Wednesday 7/2/25.)

Software version (on Special:Version page; skip for WMF-hosted wikis like Wikipedia):

Other information (browser name/version, screenshots, etc.):

https://www.mediawiki.org/wiki/Extension_talk:MultimediaViewer#Workaround_for_%22There_seems_to_be_a_technical_issue._You_can_retry_or_report_the_issue_if_it_persists.%22