Steps to reproduce
- Open images in Media Viewer, such as this one
- While the image loads, a second scroll bar appears next to the browser scrollbar (see screenshot below)
- The scroll bar disappears when the image is loaded
There should be no secondscroll bar, only the browser scroll bar.
A secondscroll bar appears while the image loads (the status bar message says ‘transferring data from upload.wikimedia.org). I can reproduce this consistently on Chrome, Firefox and Safari on Mac OS (Yosemite).