Google SERP Feature Update: there's been a net decline (only minor so far) in title tag length. Unlike previous updates, it doesn't look to be about pixel limit, but instead from Google re-writing titles in their search results. Related: seroundtable.com
As an example, here's a page that mentions various locations within the <title>. After this update, Google has refined to a single location, plus added the brand name with a hyphen. Using a "site" operator (without a query), the title snippet remains as the altered variation.
There does look to be a lot of nuance involved with this change and inconsistencies across device type, but a change looks to have taken place. It doesn't look to be as simple as Google taking the e.g. <h1> and replacing for the <title>, but there are instances of this.
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