Where does Google get site title tag from?

Can anyone tell me where the title tag displayed in Google for any branded searches comes from? I’d assume that this was the home page title but this is not what is showing up.

Here’s our situation…
Our home page title and meta are set as follows:
image

However yesterday this is what was showing on SERPS for brand name search terms.

This did however match what the “Site Name” was set as in the project settings, now I understand that Webflow used to default the site name to the site title, but as I understand it now, Webflow does not allow you to set a site title, only individual pages. So while I assumed this meant that the site name should no longer pull through as site title, I decided to change it anyway to see what happened.

So I changed site name as follows:

Then today the site title pulling through in Google is different to yesterday, but is not the same as any site name or individual page title.
image

So the question is, where is Google getting site title from in Webflow for brand name searches like this, and how do I go about changing it?

I suggest you review Google’s guidelines and guidance. How to Change Title Links in Google Search | Google Search Central  |  Documentation  |  Google Developers

Yes I am aware of these, while it is possible google does not like our title tag and has chosen to overlook it, I would be somewhat surprised since there has been no significant changes to the title of the home page recently so not sure why they would suddenly decide to overlook it.

Nevertheless I’ll make some changes to it to see if that pulls through.