UPDATED 28-MAR-2013 – see the video at the bottom of the page on “How To Block Game Invites on Facebook”.
If you’re like me you don’t want to block or delete your friends but you really don’t want to play Potato Bug or Window Seal on Facebook. You also probably don’t want to block all invitations because you (a) want to know what your friends are into and (b) you may be up really late one night and decide to join.
If you haven’t known what to do just do this:
Log in to Facebook. Go to https://www.facebook.com/appcenter/ look in the left sidebar and find the word “Requests”. It will look somewhat like Figure 1.
While you are there you can remember all those invitations you just deleted from your Notifications or you wall and revisit the dismay at your boss inviting you to play Twinkle Toes. Shiver. Once you block the app in the next step the invites are gone and you will not get further invites to play the game (or use the app).