@Stang is this the style of the edit you wanted to make prior the the whitelisting?
https://www.wikidata.org/w/index.php?title=Q109622820&type=revision&diff=1530637309&oldid=1530636710

@Xaosflux, yes.

Did a quick test on beta cluster, found something weird (not that relevant to this task though)

1. Add \blinktr\.ee\b in global Spam_blacklist - everything looks great, I got trapped when adding link https://linktr.ee/JasonSeah
2. Add another entry \blinktr\.tv\b to global Spam_blacklist, seems I did not get trapped anymore...

Is there something wrong with my operation?

Could this be because edit summaries are checked for spam, as mentioned in T15599#173812? Removed content can appear in edit summaries in the Wikidata user interface (and other scripts and tools) and there is usually no way to save with a different summary.

(if this is the reason, it should be possible to restore a revision from before the addition, if it was not there from the first revision)

For reference, edit summaries are indeed conditionally checked for spam:

// HACK: treat the edit summary as a link if it contains anything
// that looks like it could be a URL or e-mail address.
if ( preg_match( '/\S(\.[^\s\d]{2,}|[\/@]\S)/', $summary ) ) {
	$links[] = $summary;
}

For Wikidata, this is unfortunate because when you remove a piece of data ("by hand"), it is usually included in the edit summary.
Paradoxically, when the domain is put on the blacklist meanwhile, the only one blocked by the filter is the cleaner, not the spammer.

This task should get higher priority. See Chinese Garden. The official website is on the Spamlist. I can not remove the link, can not set it to deprecated. Can not do anything with it. And worst of all I can not use the whole object in articles. We have the template Sitelinks But i can not save the article due to this blacklisted P856 property.

I tired to remove this from that example wikidata entry above, it failed. Is there a different phab case for claim removal interactions with the SBL?

{

"error": {
    "code": "failed-save",
    "info": "The save has failed.",
    "messages": [
        {
            "name": "wikibase-api-failed-save",
            "parameters": [],
            "html": "The save has failed."
        },
        {
            "name": "spam-blacklisted-link",
            "parameters": [
                {
                    "list": [
                        "archive.today"
                    ],
                    "type": "text"
                }
            ],
            "html": "The text you wanted to publish was blocked by the spam filter.\nThis is probably caused by a link to a forbidden external site.\nThe following text is what triggered our spam filter: archive.today"
        }
    ],
    "docref": "See https://www.wikidata.org/w/api.php for API usage. Subscribe to the mediawiki-api-announce mailing list at <https://lists.wikimedia.org/postorius/lists/mediawiki-api-announce.lists.wikimedia.org/> for notice of API deprecations and breaking changes."
},
"servedby": "mw-api-ext.eqiad.main-5b97f6f545-2h6xx"

}

A workaround could be to first change the link to garbage and then remove the garbage.

In T296102#12038029, @matej_suchanek wrote:

A workaround could be to first change the link to garbage and then remove the garbage.

Yes, that can be done. That is not a "fix" for the technical issue. This seems to still be the original user story?

When I try to remove a link from wikibase that is on the SBL, the SBL prevents this.

Yes (to all).