Same as title. Where is the embed icon option?
Don't know what you mean.
If you want to embed a picture, see the right-click functions of the picture area in the tag panel
Google and others keep mentioning make sure embed film poster is checked. Call it Cover Art. Or whatever, but I do not see any option. What I see is the general icon Windows uses when I browse the folder using Windows Explorer.
So it is a Windows Explorer problem?
The displayed picture in WE depends on the symbol size.
If you want to use MP3tag to embed pictures - see the documentation on how to customize the tag panel
Does
come from a AI function where the AI phantasizes about product features without deeper knowledge of the application?
There is no such checkbox.
You can drag & drop cover art into the selected tracks.
From the documentation:
Contextual menu for cover art:
Or you can use an Action to import existing cover art files.
And I have hit save multiple times to emphasize, please save and show the film poster in Windows Explorer. But no such luck. I did right-click Remove cover, Add cover, and save, over and over but no poster shown in Windows.
start Mp3Tag up and it shows the cover art in the lower left window under the directory.
As far as MP3tag's influence goes: has the picture been embedded?
Could you show us a screenshot of a single selected file and the extended tags dialogue Alt-T?
And everything following that verification is a Windows Explorer problem: does it support the tag format of those files? What type of picture does it like?
And if you know that then MP3tag can probably help you to fulfill these requirements.
And I have tried JPG, PNG, WEBP. Are my steps correct? Should this work> This a 4K UHD MKV movie.
The problem may be that there are no errors in the present program but that the next program has problems to interpret the file format.
Assume that everything went smoothly.
The screenshot from MP3tag shows that a picture is embedded.
It also shows that the files are in mkv format - do you have any further specifications that suggest that the Windows Explorer supports metadata in mkv files?
If nothing else helps, try the external file folder.jpg
I found this external thread on the problem to get Windows explorer to show thumbnails:
https://www.reddit.com/r/WindowsHelp/comments/yw6s32/how_to_show_mkv_thumbnails_in_the_windows/?rdt=38073
The external thread looks to me as though the WE does not natively support MKV metadata but that you have to have a plugin/extension.
Thank you. Reviewing that now. But, as far as I can remember, and my memory is fading, once an application sets the icon Windows should honor it. Windows opens the file, extracts the icon, and displays it in Windows Explorer. But check Plex Media Server too. . .
And Plex Media Server does show images, all from its own pulls. Not showing what I embedded. That may be a Plex setting. At least it is nice to look at 
But I do like software to honor my settings, my choices. Need to review the Windows Explorer issue. Did see a recent comment about Windows will honor MKV icons. . .
Thank you for confirming it is embedded.
The easiest way would be to compare a file where it works with one where it does not.
At the moment I have two cases it does not work. Windows, and Plex Media Server. By chance, know the setting to tell Plex to pull the icon from my TOY_STORY.mkv file?
I am using Windows 11
This is referring to the application icon for the default program allocated by file type. This does not apply specifically to media files and replacing the metadata artwork.
There is a setting in Plex to "prefer" embedded artwork. I can't recall where in the options that can be set but it is there. The challenge is once Plex has built its library it is very difficult to get it to update it from external changes.
Explorer has very limited support for mkv. And even less for mkv metadata.