You can always take a look at the release notes
, its usually the top item under the general discussions part of the forum. At the bottom you'll see a link to "Known issues" - those two should almost always give you an idea what's fixed and what's not.
With regards to your issue:
Yes this bug was introduced with SF v4.3, and there was a hotfix for it, that part has been fixed. However, there are still two (unrelated) image quality issue floating around, which was not fixed in Sitefinity v4.4 (also mentioned under the known issues)
One of these will only be introduced if you manually added a RadCompression line to your web.config to even further compress the your data calls, so that's probably not the case.
There has been no fix introduced for these in SF v4.4. PITS
shows the progress currently as open, but that's not always a good indicator, so shortly before a new release.