After open a page in the Pages plugin, editing it, and saving it, what we are landing on is an error screen (paths edited to protect the guilty):
	Uncaught Exception
	Message: Unknown condition type: --
	Location: /interface/default/objects/PrivilegeEditingUI.php[465]
	Trace:
	#0 /interface/default/objects/PrivilegeEditingUI.php(208): PrivilegeEditingUI->ExtractPrivilegeSetFromFormData(Array)
	#1 /plugins/Pages/pages/EditPage.php(279): PrivilegeEditingUI->GetPrivilegeSetsFromForm()
	#2 /lib/ScoutLib/ApplicationFramework.php(540): include('/htdocs...')
	#3 /index.php(148): ApplicationFramework->LoadPage('P_Pages_EditPag...')
	#4 {main}
	Going through the trace, not finding much helpful. Other than if i log $FormData from PrivilegeEditingUI.php there are indeed a lot of double dashes in it.
		    function ExtractPrivilegeSetFromFormData(array &$FormData)
		    {
		error_log(print_r($FormData, true));
			Array
			(
			    [0] => --
			    [1] => --
			    [2] => --
			    [3] => 
			    [4] => --
			    [5] => --
			    [6] => --
			    [7] => 
			    [8] => --
			    [9] => --
			    [10] => --
			    [11] => 
			    [12] => --
			    [13] => --
			    [14] => --
			    [15] => 
			    [16] => --
			    [17] => --
			    [18] => --
			    [19] => 
			    [20] => --
			    [21] => --
			    [22] => --
			    [23] => 
			    [24] => --
			    [25] => --
			    [26] => --
			    [27] => 
			)
		What could be happening here?


Is there any chance you've disabled javascript in your browser for P_Pages_EditPage? The PrivilegeEditingUI is using client-side JS to construct the priv editor and present only operators and values that make sense for the selected fields in each row. The HTML provides a template row that the JS uses... but it looks like your form values are just the unmodified template row.
It was apparently a JavaScript error, thank you. We were getting 403s for minified files. We turned off minification and now the page operates properly.