Link List Module is not saving 3rd language translation

[zplus2]

When I am trying to set up translations in Design - Link widget - it works ok for SK and EN language, but CZ language is not saved, it remains empty.

I change the name of the block for all 3 languages, SK and EN are saved, CZ leaves the field empty.

Also, Custom Content - English and Custom Content Slovenský (SK lang) are saved correctly. CZ is again empty after saving.

There is no error.

PS 1.7.4.3 and Link List module v. 2.1.5