You can set Page Property （Visualforce <apex:page> Property, etc.） from Apex Class Extension feature. Here is a list of configurable setting and its order of Priority.

Setting Name	Definition	Order of Priority
p_cache	With or Without cache	Apex Class Extension (set within init) URL Parameter Setting Apex Class Extension (set from constructor) Studio Screen setting *For example: The “False” setting of the Studio Screen will be overwritten as “True” if the Apex Class Extension is set as “True.” This is because the Apex Class Extension’s priority is higher than the Studio Screen setting.
p_contentType	MIME Contents Type
p_docType	DTD
p_expires	Cache Expiration
p_language	Language indication
p_rendered	Show/Hide Page
p_setup	Set default style
p_showChat	Chat widget indication
p_standardStylesheets	Add Salesforce CSS
p_wizard	Salesforce Wizard Page CSS
p_showHeader	Show/Hide Header	Studio Screen Apex Class Extension (set within init) URL Parameter Designation Apex Class Extension (Set from constructor)
p_sidebar	Show/Hide Sidebar
p_isPdf	ON/OFF PDF output
p_pdfPageSize	Page Size
p_pdfOrientation	Page Orientation
p_pdfMargin	Page Margin Size

サポートされていないブラウザーです