Telegram side tab sometimes disappears for few seconds or closes

After recieving new message notification in Telegram or Whatsapp used in messenger tab, but hidden at the moment and clicking on the message notification popup, tab splash screen appears for a second before messanger opens.

@leocg It's plus 1 click, if sidebar is not used.

Where the button to simply open closed page? It was earlier in place of "Search in tabs" button.