Export frame to Pictures...where?

In Photos app, while playing a movie, if you select the gear in player controller appear a menu list.

Selecting "Export frame to Pictures" (or something like that) Photos should save the frame... but I can't understand where!

It's not in pictures folder and not in Photo's moments so...where is it saved?

You can find the frame in your Picture folder under the name Frame_something.tiff. Then you can import that frame in the Photos app like a normal picture.

The TIFF for the frame you exported will be within /Users/[Your Username]/Pictures.

Wouldn't it be nice if the export were in a format that Photos could import! And if there was an option just to create a still image in Photos!

Instead, you can do your exports, then go to the finder, select them all, open in Preview, select them all, export as PNG format (to the Desktop), then drag them from the desktop into Photos. Phew!