28.12.2017 00:39
On the top menu panel, click on Tag tab → Allow file tagging to show tagged files only. Then select a picture and use Tag / Untag feature from the context menu (see pic. 1). It will add a red box as it show on the picture 2.
You can easily view only tagged files by clicking on the button named Show Tagged Files Only (see pic. 3). Also, you can use Tag → Show Tagged Files Only (Alt + Q) as the alternative option.