Open all grouped windows with Alt-tab

I wondered if it is possible to open all grouped windows of one application at одиннадцать with Ubuntгs (well, Unity's) alt-tab mechanic. What I мочатся is the following вступите в брак: https://i.imgur.com/ixHKwUM.png (can't embed the image схвати в new account).

I have two documents open in the PDF viewer and arranged them side by side. Now I переключатель to another application (say Латекс) to do something and want to переключатель back to the PDFs to look at them. The стандарт alt-tab only opens one of the two PDFs and I have to bring the other into focus manually, which is annoying (the same also happens when you click on the icon).

Seems straightforward but I haven't figured it you yet. Хан you конфигурировал Unity to just open all windows of an application when clicking or alt-tabbing to it? In the meantime, I open both the documents in another workspace and переключатель between workspaces with Ctrl+Alt+Arrow key.