Main: Clear cache and storage data only when the last window is closed

This prevents the CONSENT cookie from being deleted after a window
is closed by the user, making it so that the user can no
longer load the comment section.

src/main/index.js

@@ -327,6 +327,8 @@ function runApp() {
     })
 
     newWindow.on('close', () => {
+      // Clear cache and storage if it's the last window
+      if (openedWindows.length === 1) {
         newWindow.webContents.session.clearCache()
         newWindow.webContents.session.clearStorageData({
           storages: [
@@ -340,6 +342,7 @@ function runApp() {
             'cachestorage'
           ]
         })
+      }
     })
 
     newWindow.on('closed', () => {