"Share not found" error

I have an issue on forum.mudita.com. From some time (few months) the share button for specific post under topic is not working. It was after some update (don’t remember which one). I’m using up-to-date discourse instance (2.4.0beta6).

My settings for post actions:
image

There’s no action after clicking “share” button, nothing happens. Only an error appears in the browser’s console:

share not found
_application-5d69c42124908eb6b41549efae9db9b1df26741f3a45075c6bfd603bb5267a42.js:76184 
value @ _application-5d69c42124908eb6b41549efae9db9b1df26741f3a45075c6bfd603bb5267a42.js:76184
(anonymous) @ _application-5d69c42124908eb6b41549efae9db9b1df26741f3a45075c6bfd603bb5267a42.js:76251
value @ _application-5d69c42124908eb6b41549efae9db9b1df26741f3a45075c6bfd603bb5267a42.js:76218
value @ _application-5d69c42124908eb6b41549efae9db9b1df26741f3a45075c6bfd603bb5267a42.js:76245
click @ _application-5d69c42124908eb6b41549efae9db9b1df26741f3a45075c6bfd603bb5267a42.js:68092
(anonymous) @ _application-5d69c42124908eb6b41549efae9db9b1df26741f3a45075c6bfd603bb5267a42.js:70283
(anonymous) @ _application-5d69c42124908eb6b41549efae9db9b1df26741f3a45075c6bfd603bb5267a42.js:70206
value @ _application-5d69c42124908eb6b41549efae9db9b1df26741f3a45075c6bfd603bb5267a42.js:76218
d @ _application-5d69c42124908eb6b41549efae9db9b1df26741f3a45075c6bfd603bb5267a42.js:70205
(anonymous) @ _application-5d69c42124908eb6b41549efae9db9b1df26741f3a45075c6bfd603bb5267a42.js:70282
dispatch @ _ember_jquery-7dfac344d893a6c10c016353b994db2c6f42af630322ea6da3399c220fcc50ed.js:5251
v.handle @ _ember_jquery-7dfac344d893a6c10c016353b994db2c6f42af630322ea6da3399c220fcc50ed.js:5058

Styles are highly customized, but the button’s widget is untouched. I can’t provide full repo here, but can paste some parts of code if needed.

You can try it for example on Stretch Goal Question - Mudita Products - Mudita Forum by clicking the share button image under the main post or under the topic’s reply post.
You can also see that image action for whole topic (under last post) is working well.