That 2nd part, in the "Update", doesn't sound like a forms issue - you're seeing a problem in a page that calls a template, with no form involved. It sounds like there's an error in the property name(s) in the template. My guess is that that's what is causing the form problems as well - because there's an error in the template, the form can't figure out what values to use for the dropdown inputs.

You were indeed right! I did not see that I have to apply changes at two positions on the Wiki page defining the form - actually not the form, but the *template*. My sincere apologies!

Please note that this is confusing.

I have two pages:

• A form Wiki page.
• A template Wiki page.

The form to enter data displayed by Special:FormEdit/HWComponentMemoryForm/.... contains the definitions but Special:FormEdit apparently looks at the template in order to learn which properties to use and which type they are. I understand the necessities, but I intuitively always assumed the form definition is for presenting the form to the user, and the template is intended for presenting a non-edit view of the data. That at least would seem to be natural somehow - which seems not to be the case here. Having the form rendering logic looking into the template is ... confusing. I would never have expected such a design. And I always named the identifiers used by the form identical to the properties so I never thought about this so thoroughly. That's why I was not able to detect this error myself in the first place.

Of course it's too late to change the software design now. It would break compatibility with a lot of Wikis now. I understand that. But maybe you want to leave a hint in the documentation of the extension for other people to understand the mechanics here as well.

You can safely close the issue. Thank you for your help!