TinyMCE in Structures will expire?

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Hi donShakespeare

on all pages where the Structures extra is installed there is now many error messages popping up, saying:

"Your access to TinyMCE will expire on 25 Februrary 2021. Please either contact your administrator or upgrade your account using the instructions available here." (Linking to this page.)

Does Structures use the RTE that is set as the main RTE in modx system settings, or does Structures bring its own RTE? I'm not completely sure, if this is an issue of Structures, that's why I am asking.

I would appreciate any help or hint! :)

Thank you and best regards! Lotta