Steps to replicate the issue:

• Create a form as below:

{{{for template|Page}}}
Country:
{{{field|Country|input type=dropdown|property=Country}}}
City:
{{{field|City|input type=dropdown|values dependent on=Page[Country]}}}
{{{end template}}}

• Create a set of Page pages with Country and City fields filled with data
• Try to create a new page via a form
• Set Country to something

What happens?:

• The City dropdown contains no options

What should have happened instead?:

• The City dropdown should be populated with options when Country input value is changed

Software version:

• PageForms 4.8 (2e84936)
• MediaWiki 1.35.8 (19c5cf3)