Movieclip is not looping

Since yesterday I have an issue with my Animate cc (HTML5 Canvas). My movieclips sometimes is not looping. Here the link on fla file with example:

Not Loop (Google Drive)

There is movieclip "arrows" that plays only once.

And here the same movieclip is looped:

Loop (Google Drive)

UPDATE1: When i publish my project, in generated js file i got this lines adding my movieclip to the library:

(lib.arrows = function(mode,startPosition,loop) {  
if (loop == null) { loop = false; } this.initialize(mode,startPosition,loop,{});

And i understand that this part don't let looping a movieclip:

if (loop == null) { loop = false; }  

But what i dont understand, is why this part sometimes is added and sometimes not. It's so strange. It is added with no reason on my opinion, because i create my movieclips as usual.

Help me please to understand what's the problem.

I was find an answer. Maybe it's a bug. But when i inside a movieclip in my workspace and publish a project (with checkbox "Loop timeline" not checked), i got this movieclip is not looping. When i going next level up to the Scene and then publish a project (with checkbox "Loop timeline" not checked), it's ok, movieclip is looping.