Looks like in 'addAdditionalParamsToUrl' we only iterate widget's own data attributes (at least I couldn't find a scenario where this.options.data is not undefined which might be a separate issue to investigate).
So when it comes to common data attributes (data-url, data-title), we should probably only mark them as 'known' if having them specified on service level is officially supported and has an effect on the outcome (so if it's actually used by service in which case it also overrides url / title specified on parent level).
For example, facebook service doesn't use 'title' when constructing a share url, which results in:
not throwing a warning for data-title specified in .likely (although, there is no way for user to find out that title is not going to be used, but it can probably be considered out of scope here)
throwing a warning for data-title specified in facebook div (here we have a clear intention of having a custom title for a particular service, so a user probably should know it's going to be skipped)
Related to #172 (initial change for 2.5)
Looks like in 'addAdditionalParamsToUrl' we only iterate widget's own data attributes (at least I couldn't find a scenario where this.options.data is not undefined which might be a separate issue to investigate).
So when it comes to common data attributes (data-url, data-title), we should probably only mark them as 'known' if having them specified on service level is officially supported and has an effect on the outcome (so if it's actually used by service in which case it also overrides url / title specified on parent level).
For example, facebook service doesn't use 'title' when constructing a share url, which results in:
.likely(although, there is no way for user to find out that title is not going to be used, but it can probably be considered out of scope here)