thetgc wrote: ↑
Fri May 03, 2019 4:42 pm
Certainly something may have changed with Facebook but then it would also have had to change with Twitter and LinkedIn because sharing images to those networks no longer works either so my money is on something that changed in phpbb.
Well crap, never mind the technical response below.
None of the external sites can get to your images?
This seems to make it even more likely to be a case of "my phpBB site isn't allowing bots/guests to access attachments."
Not having Guest user permission "Can download files", or not having the Guest forum permission "Can download files" in the specific forums, would block not-logged-on sessions from accessing the images. Same applies to Bots group, if whatever Facebook connects as is registered as a bot on the site.
Very important to rule that out next, before anything else.
david63 wrote: ↑
Fri May 03, 2019 4:31 pm
+1 Indeed, there is no way to assume the change in behavior was on one side versus the other. Both still have to be considered as a potential root cause, even if you want to take the extension out of the equation.
thetgc wrote: ↑
Fri May 03, 2019 3:40 pm
All the extension is doing is taking the existing url and "posting" it to whatever social media you have chosen.
I follow you on the idea of trying to separate out "what is the extension behavior" versus "what is the Facebook behavior against phpBB." Not sure the reality allows them to be separated quite that easily though.
"All it does is submit the URL to Facebook" correctly describes what happens when you hit the actual share button. But the extension has done a bunch of work and generated a bunch of tags in the page before that, regardless of whether anyone ever actually hits the share button or not.
With the extension installed, the image to be presented isn't "well, whatever Facebook decides it wants to scrape off the page presented by this phpBB URL." The extension's PHP code has already looped through the post images and explicitly created OpenGraph tags with the first phpBB post's image as "og:image". (But without og:image:height and og:image:width, hence the warning.) Facebook didn't "do that", the extension did that.
Whether you then hit the Facebook share button on your phpBB page to send the URL -- versus entering that URL manually into the Facebook Sharing Debugger -- both actions are then asking Facebook "please read the phpBB page at this URL and honor any OpenGraph hints that exist in it." Those OpenGraph tags were created by the extension in both cases.
To test "What is the behavior of Facebook against phpBB without the extension and manually submitting the URL", you would have to disable the extension entirely; not just "avoid hitting the share button from within phpBB." i.e. You need to have the OpenGraph tags removed from the page header, and then see what Facebook does when presented with the same phpBB URL.
But whatever Facebook behavior occurs once you disable the extension, you still wouldn't be able to immediately say "that's different than how Facebook behaved against phpBB 3.2.4." Because the extension was still enabled when you were running phpBB 3.2.4. You would need to test against a phpBB 3.2.4 server without the extension running to see if "Facebook behavior changed because of something that changed in how phpBB presents its page between 3.2.4 and 3.2.6."
Note that the point of "can Bots/Guests even see the attachments to the posts on your site" still applies in all
of those cases. Since it leaves Facebook powerless to get any image data regardless of whether it wanted to manually scrape it off or not, or whether og:image explicitly told it to or not. If Facebook can't access the images on the page on your specific site, it would answer every single question here. Which doesn't mean it's the problem; it's just something important to rule out.
Wish I could be better help, but I don't have a Facebook account to even see what options the Facebook Sharing Debugger is offering you. If we're lucky, someone who actually does this might have experience to contribute here. Or someone who subscribed to the extension support thread sees it, which is an additional reason posting there could be beneficial and appropriate too.