Feature summary (what you would like to be able to do and where):
Users should be able to specify the relative width of an image like [[File:Example.jpg|100%]]
Use case(s) (list the steps that you performed to discover that problem, and describe the actual underlying problem which you want to solve. Do not describe only a solution):
I would like the image to take up the full viewport regardless of screen width.
Benefits (why should this be implemented?):
Responsive UI.
I would like the image to take up the full viewport regardless of screen width.
I don't necessarily see why an editor of a page should impose that onto all and any users? Also, I'm not sure how to interpret the two words under "Benefits"...
We can't have this in the way current items are designed.
The better way would be to provide a size hint, that conditionally can be adhered to by skins.
This would require defining up front EXACTLY what the behaviour of such elements should be, or we end up with another cluster %# like upright. (and yes, there is a ticket for that somewhere....)