Dec 8 2018
I am really not very familiar with the procedures and mostly just looking for a way to efficiently upload from a smart phone.
Feb 1 2017
@ Jdlrobson, if by "gadgets" you mean browser add-ons, I am using these:
One-click translate page
Right click translate
Your last comment, Tgr, might explain this seemingly erratic behaviour.
Jan 24 2017
Sorry for getting back so late.
Jan 20 2017
It happens at random pages at random times.
For exampled selecting images from this page: https://commons.wikimedia.org/wiki/Category:Genetic_studies_on_Mestizo,
the first image opened here: https://commons.wikimedia.org/wiki/File:Average_continental_ancestry_of_Bolivians_analyzed_using_a_panel_of_46_AIMs.png
and the next image I tried opened in the Media Viewer: https://commons.wikimedia.org/wiki/Category:Genetic_studies_on_Mestizo#/media
then, going back and clicking on the first image again, it also opens in the Media Viewer: https://commons.wikimedia.org/wiki/Category:Genetic_studies_on_Mestizo#/media/File:Average_continental_ancestry_of_Bolivians_analyzed_using_a_panel_of_46_AIMs.png
Going on to to a different category right afterwards and clicking on images there, sometimes Media Viewer will appear, sometimes not.