This has happened to me on a few occasions, the issue that causes it is that every so often a page will refresh itself to a certain extent. I believe this is to keep things updated for every internet page even if nothing happens. Unfortunately it's something that will most likely happen every now and then due to the refresh, it's not something you can turn off either. I do admit it's a pain, but at least it's not as hard to get in game as it was previously.