Likes the video, reel or post on screen with its own heart — the side rail's, never a comment's — and checks the heart turned on: one tapped but never seen to turn on is a failure, "not confirmed". Never taps a like already given, which would take it back. Puts away an open sheet first; an ad is left alone. A feed of posts, with no buttons beside a full-screen video, is not supported and says so.
No inputs 28 steps
Run Close the sheet → closed if it fails, carry on Stop, it failed · The sheet over the video would not close. · hand back closed › value Read the screen → screen if it fails, stop Stop, it failed · This one is an ad. · hand back this one is an ad Find the icon like · on the post · looking twice → heart if it fails, stop If all of not heart › found is yes +1 Stop, it failed · This is not a video with its buttons beside it — a feed of posts, say — and this only works on one: open a video or reel first. · hand back not a video with its buttons beside it Stop, it failed · No like button on this screen. · hand back no like button on this screen Finish · Already liked. · hand back already liked Tap heart · then move the pointer away if it fails, stop Find the icon like · on the post · already on · waiting up to 2.5 s → liked if it fails, stop Finish · Liked. · hand back liked Run Close the sheet if it fails, carry on Find the icon like · on the post · already on · looking twice → late if it fails, stop Finish · Liked. · hand back liked Find the icon like · on the post · moved away from heart · looking twice → moved if it fails, stop If all of moved › found is yes +1 Tap moved · then move the pointer away if it fails, stop Find the icon like · on the post · already on · waiting up to 2.5 s → liked if it fails, stop Finish · Liked. · hand back liked Stop, it failed · Tapped like, but could not see it turn on: not confirmed. · hand back tapped like, but could not see it turn on