Can't find the PDF viewer

If you cannot see a split screen containing the Overleaf editor and PDF preview, or the PDF preview or Overleaf editor is hidden from view, you can use the Layout menu to quickly rearrange and refresh your Overleaf workspace.

For example, to restore a split screen view, select Editor & PDF from the Layout menu as shown below. A checkmark is placed next to the currently active option:

For more information on the Layout menu see the Overleaf help page How to use the Overleaf layout menu.