All travel restrictions are lifted, since July 1st, for nationals from the EU/EEA countries (including UK).
That means that if you are a national or resident of the above mentioned countries, you can now travel to Croatia without quarantine, PCR test or any other restrictions.
From July 10, 2020, all other foreign nationals not mentioned above can enter Croatia for business or tourist reasons (with paid accommodation reservation), if they have a negative PCR test, not older than 48 hours, otherwise they have to self-isolate for 14 days. Read more on the official Croatian coronavirus update website.
All travelers, no matter the country of origin, must fill this online form prior to arrival, so that the border control will take much less (because they will already have all the necessary information in their system, which will speed up your border processing time).
Here is an update from the border police, dated July 11, reported by the main English portal in Croatia, Total Croatia News.
As for while you are in Croatia, masks are mandatory in shops, public transport and hairdressers.
Looking forward to having you here and make sure to visit our shops, when in Split! Here are the Break Time shop locations.