> The default behavior in 4.12.5 suggested otherwise so there is some inconsistency here.
It never showed up in the content browser. They are not uassets so they content browser has no idea about them. This functionality will not be supported at this time.
> When you add a Startup movie in 4.12.5 it prompts you with the dialog window that a change to source files were detected, would you like to import.
This was a bug. The fact that it is not happening now is a good thing so the current functionality is correct.
Startup movies are not being copied to the Content/Movies directory within the Content Browser. This can be confusing to users as it is not editable, but still functions correctly as a startup movie.
I believe the source of this issue is a missing dialog window that notifies users "a change to a source content file has been detected, Would you like to import it?" This does not appear in the 4.13.1 engine version. I have attached images for clarification.
1. Download the attached movie file.
2. Create new blank project without Starter Content.
3. Navigate to Project Settings/Movies/ and press the [Image Removed] symbol to add a new movie.
4. Choose the downloaded movie file.
Outcome A prompt appears to copy the movie file, but the movie is not copied to the Content/Movies directory in the Content Browser. It does exist in the Unreal Projects directory though.
Expected You should be prompted to copy the movie file to your project via a dialog window, and after selecting 'Yes' you are able to see the movie in your Content/Movies directory within your Content Browser as well as your Unreal Projects directory.
Note I noticed this issue does not actually affect playback of the Startup movies when run in Standalone.
Head over to the existing Questions & Answers thread and let us know what's up.