"Let HTC Sense access Facebook"

Is the app up to date? Do you use blink feed?

 

Easy Fix.....

delete the Facebook app....

I only use a browser to read FB, you would be amazed how much cleaner the phone is now... not hanging up with unexplained crap going on.... doesn't ask me to merge my Contacts, etc...

 

I guess it is to do with HTC Sense's FB integration. What in detail talks to FB I don't know: HTC's own social app, or Blinkfeed, or something else - I never use this and as a rooted user I remove most of it. I doubt it shares stuff automatically, more likely to be able to integrate data from your FB with their apps, but as I say I don't actually use it (either FB software or BlinkFeed).

To be honest I was never bothered by this message either, even before I modified the software, so I don't know what it is you are doing that's bringing the message up repeatedly. But maybe try disabling the "Facebook for HTC Sense" (or similar name) app, check your BlinkFeed settings to turn off Facebook integration, maybe even check the settings of other HTC apps (e.g. Contacts) to see whether they are requesting access to FB data. But the HTC Sense launcher or Blinkfeed would be the most likely things. You could even try a long press on the notification to find out which app is producing it, then either go into that app's settings (if it's something you use, such as the launcher) or disable it if it's something you don't use.

 

You can long-press the notification, and then there is a toggle switch to "Block." "Never show notifications from this app."

You can also go into Apps (All) and you'll see *two* apps - one named "Facebook" and the other named "Facebook for HTC Sense." It's that second app, Facebook for HTC Sense. You can click it, and un-check "Show notifications." This will not disable the *normal* Facebook app from giving you notifications, if you have them enabled.

To answer your question about what it does, the app description says "This app can access the following on your phone. In order to improve performance and reduce memory usage, some of these permissions are available to Facebook for HTC Sense because it runs in the same process as Google+ for HTC Sense, LinkedIn for HTC Sense, Twitter for HTC Sense and Instagram for HTC Sense."

Long story short, HTC tries to suck content from all those places and put it into BlinkFeed. (That weird screen if you keep swiping to the leftmost desktop screen.) If you don't use BlinkFeed, you should probably disable all these.