Steps to replicate the issue (include links if applicable):

• Go to a talk page and start creating a new topic using the new topic tool or reply using the reply tool.
• Switch to source mode.
• Type out some stuff, including two line spaces to separate out paragraphs as normal.
• Place the cursor in the second paragraph.
• Use the left arrow key to move the cursor back to the first paragraph.
• Use the right arrow key to move the cursor back to the second paragraph.

What happens?:
It takes an extra press of the key to move the cursor, during which the cursor moves only a pixel or two. This seems to be due to some sort of hidden element.

What should have happened instead?:
The extra key press should not be required.