Is thump_path always the same as the url? If so then remove it in the Media manager Api, but I think that thump is for a thumbnail provided by some cloud storage providers (s3, dropbox)

Is thump_path always the same as the url? If so then remove it in the Media manager Api, but I think that thump is for a thumbnail provided by some cloud storage providers (s3, dropbox)

No, but that is not the fix here. Thumbpath is for non local adapters. This fix is the call, when someone either insert an image into the editor (via the image plugin) or uses the image media field (like the intro image). In this case only the "url" is relevant. I search the whole Joomla for Joomla.selectedMediaFile.thumb which is never used, I assume, that is is a leftover or a typo?

So the value filled in has to be Joomla.selectedMediaFile.url to functional.

So the value filled in has to be Joomla.selectedMediaFile.url to functional.

Yes, you're right. FWIW the thumb part shouldn't be there but rather in

updatePreview() {
  if (['true', 'static'].indexOf(this.preview) === -1 || this.preview === 'false' || !this.previewElement) {
    return;
  }

  // Reset preview
  if (this.preview) {
    const { value } = this.inputElement;

    if (!value) {
      this.previewElement.innerHTML = '<span class="field-media-preview-icon"></span>';
    } else {
      let thumb = Joomla.selectedMediaFile.url;
      this.previewElement.innerHTML = '';
      const imgPreview = new Image();

      if (Joomla.selectedMediaFile.thumb) {
        thumb = Joomla.selectedMediaFile.thumb;
      }

      const mediaType = {
        image() {
          imgPreview.src = /http/.test(thumb) ? thumb : Joomla.getOptions('system.paths').rootFull + thumb;
          imgPreview.setAttribute('alt', '');
        },
      };

      mediaType[this.type]();

      this.previewElement.style.width = this.previewWidth;
      this.previewElement.appendChild(imgPreview);
    }
  }
}

Is this on hold or should it still be tested?

Can a maintainer please set the label "Conflicting Files"?

This should be already fixed by now

This pull request has automatically rebased to 4.2-dev.

What should we do with this PR @bembelimen @dgrammatiko

If #38805 is merged then also local adapters would have a thumb so this PR would break the other one.