Editor hangs in Animation Montage [not solved]

When doing the tutorial (3rd person template), I was playing with the notifications, when suddenly the Editor starts to hang forever. On that moment the only option was to force kill the Editor and lost part of my work :(. I

Even worse now, I can’t open the montage anymore I saved soon enough. The Editor keeps hanging when I try to open the Montage view! So, here ends my story using the Unreal Editor from now.

The file which is causing my editor to hang/crash is the PunchingMontage.uasset (Animation Montage):

EDIT:
I know when it happens exactly. The editor only hangs forever when I added the notifiers in combination with the default ‘Preview’ mode in the Animation Montage. On that moment the editor will hang. Try to re-open the Animation file, if it’s not yet hanging. For sure it should hang now.

I’m not the first person who report this issue:

and here:

and here as well:

It has a bug report: UE-21313. PLEASE HELP!

OS: Linux Mint 17.3 (but the bug is also present under Windows)

Screenshots when it hangs:

The UE4Editor launcher start crashing, bleh. Signal 11. I guess because of this hang.

See core dump file:

You can playback using (in theory):

gdb ./UE4Editor -c [corefile]

Bug is already report to be UE-21313. When you switch to branching point as notifier the editor will hang. Using v4.10 of the Editor this issue is still present. It’s not depending on the platform both Windows & Linux suffer from this issue.

Bottom-line: we can’t use animation montage.

I’ve added your info to UE-21313

Thanks! I has something to do when setting a notifier of the type Branching Point.