Remove references to isFeedProvider.

Account/Sources/Account/WebFeed.swift

@@ -152,14 +152,9 @@ public final class WebFeed: Feed, Renamable, Hashable {
 	
 	public var isArticleExtractorAlwaysOn: Bool? {
 		get {
-            if isFeedProvider == true { return false } // not an option for FeedProviders
+            metadata.isArticleExtractorAlwaysOn
-			return metadata.isArticleExtractorAlwaysOn
 		}
 		set {
-            if isFeedProvider == true {
-                metadata.isArticleExtractorAlwaysOn = false
-                return
-            }
 			metadata.isArticleExtractorAlwaysOn = newValue
 		}
 	}

Mac/Inspector/WebFeedInspectorViewController.swift

@@ -139,10 +139,8 @@ private extension WebFeedInspectorViewController {
 		updateNotifyAboutNewArticles()
 		updateIsReaderViewAlwaysOn()
 		windowTitle = feed?.nameForDisplay ?? NSLocalizedString("Feed Inspector", comment: "Feed Inspector window title")
+		isReaderViewAlwaysOnCheckBox?.isEnabled = true
 		view.needsLayout = true
-		if let webfeed = feed {
-			webfeed.isFeedProvider ? (isReaderViewAlwaysOnCheckBox?.isEnabled = false) : (isReaderViewAlwaysOnCheckBox?.isEnabled = true)
-		}
 	}
 
 	func updateImage() {

Mac/MainWindow/MainWindowController.swift

@@ -1145,13 +1145,8 @@ private extension MainWindowController {
 			}
 			
 			if let webfeed = currentTimelineViewController?.selectedArticles.first?.webFeed {
-				if webfeed.isFeedProvider {
-					toolbarButton.isEnabled = false
-					return false
-				} else {
 				toolbarButton.isEnabled = true
 			}
-			}
 
 			guard let state = articleExtractor?.state else {
 				toolbarButton.buttonState = .off
@@ -1177,13 +1172,8 @@ private extension MainWindowController {
 			}
 			
 			if let webfeed = currentTimelineViewController?.selectedArticles.first?.webFeed {
-				if webfeed.isFeedProvider {
-					toolbarButton.isEnabled = false
-					return false
-				} else {
 				toolbarButton.isEnabled = true
 			}
-			}
 			
 			toolbarButton.state = isShowingExtractedArticle ? .on : .off
 

Mac/MainWindow/Sidebar/SidebarViewController+ContextualMenus.swift

@@ -240,8 +240,6 @@ private extension SidebarViewController {
 		}
 		menu.addItem(notificationMenuItem)
 
-		
-		if !webFeed.isFeedProvider {
 		let articleExtractorText = NSLocalizedString("Always Use Reader View", comment: "Always Use Reader View")
 		let articleExtractorMenuItem = menuItem(articleExtractorText, #selector(toggleArticleExtractorFromContextMenu(_:)), webFeed)
 
@@ -251,8 +249,6 @@ private extension SidebarViewController {
 			articleExtractorMenuItem.state = .on
 		}
 		menu.addItem(articleExtractorMenuItem)
-		}
-		
 
 		menu.addItem(NSMenuItem.separator())