Is there a possibility to add textarea parametr when writing new extension?

Hi,
I am writing new extension to inkscape as part of my bachelor thesis and I ran into a problem. I need to be able to insert larger text as a parametr (option) in extension UI. but as far as I studied all the INX and Inkscape extension documentation I haven't found the right way to do it. According to documentation, there are only two possible text inputs (string and description) but no one meets my needs.
My question is : Are there any options how to solve my problem? Is there a way to have textarea input in extension UI ? And if it is not, how long could it take to add this functionality?
Thank you for your reply.

Best regards,
Lukáš Haberzettl