Opening a new tab in Safari sometimes downloads an empty file
Occasionally, when I try to open a new tab, either by pressing command-T or the + button, Safari downloads a file. The file is usually named "unknown", doesn't have an extension, and does not contain anything when I open it with TextEdit or Nano. It's really annoying to have to delete a file every time I want to open a tab. Please help.
MacBook Pro Retina