Update 15 January 2020 confirmed upon appeal (more later).
Hotlinking is explained at para 17 of  EWHC 550 (Ch) Wheat v Alphabet /Google Inc and Monaco Telecom. (Cross-reference is also made to the related main case against Monaco Telecom,  EWHC 3150 (Ch)). The principal claim against Monaco Telecom is that it has broadcast, and continues to broadcast, an unauthorised duplicate of theirearth.com – claimant’s website. Google is involved in the litigation because claimant alleges that Google’s search engine algorithm has done little to address hotlinking practice, which, it is said, facilitates copyright infringement.
Both cases are a good example of the standards for serving out of jurisdiction, essentially, to what degree courts of the UK should accept jurisdiction against non-UK defendants (here: with claimants resident in the UK). The Brussels I Recast Regulation is not engaged in either cases for neither Monaco nor Alphabet are EU based.
Copyright aficionados are best referred to the judgment to appreciate its impact. The judgment essentially confirms that other than in a B2C context (particularly where EU law applies and privacy is involved), suing (for tort) Google or indeed internet companies not headquartered here, is not an easy proposition.