I have set a bookmark within QGIS and would like to set another bookmark just slightly east of the current one but with the same scale and north-south extent. If I use the pan tool the north-south extent changes because I can't hold my hand that still. I don't see scroll bars in the window and the arrows on the keyboad go too far to the east. Is there any other way I can shift the window slightly to the east without changing the latitude?
You can use pan tool to move the extent, save the bookmark and than rewrite yMin and yMax values to required north-south extent.
Note: This is handy only if you have a few bookmarks. If you need a lots of them it will be better export a .xlm bookmark file, do some find and replace for yMin and yMax and import .xml file back.