Cannot translate Display Header Label

Hi,
I am using Easy Table of Contents together with PolyLang.
PolyLang has the capability to allow translation of text strings, but Easy Table of Contents does not appear to expose the Display Header Label text string to PolyLang.
I can of course switch the Display Header Label off and add my language-specific heading outside of the Table of Contents block but this has other consequences, one of which is that my heading appears even where the TOC is not shown.
How about adding this capability? Please?

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