Skip e2ee warn logout prompt if user has no megolm sessions to lose

Author: t3chguy

src/components/structures/UserMenu.tsx

@@ -190,11 +190,18 @@ export default class UserMenu extends React.Component<IProps, IState> {
         this.setState({contextMenuPosition: null}); // also close the menu
     };
 
-    private onSignOutClick = (ev: ButtonEvent) => {
+    private onSignOutClick = async (ev: ButtonEvent) => {
         ev.preventDefault();
         ev.stopPropagation();
 
-        Modal.createTrackedDialog('Logout from LeftPanel', '', LogoutDialog);
+        const cli = MatrixClientPeg.get();
+        if (!cli || !cli.isCryptoEnabled() || !(await cli.exportRoomKeys())?.length) {
+            // log out without user prompt if they have no local megolm sessions
+            dis.dispatch({action: 'logout'});
+        } else {
+            Modal.createTrackedDialog('Logout from LeftPanel', '', LogoutDialog);
+        }
+
         this.setState({contextMenuPosition: null}); // also close the menu
     };