Improving How We Brand and Customize Themes
Since this is on a rapid rollout over the next fifteen days starting from September 5th, 2023, we can only deduce so much from this announcement until we have the ability to test it. However, the verbiage on the Google Sites team post gives us the idea that we can "expand" the use of templates considerably.
Currently we can import themes, which changes all sorts of settings like fonts, colors, sizing, images and more. It looks like this update will break down some of the limitations where we saw changing themes fall short. It appears we can now exercise greater control on the page layout, including custom site width and frames.
Here are some of the expanded capabilities hinted at:
We see the text automatically realigns, or justifies, based on the chosen theme.
The header was previously aligned center, then aligns left and perhaps the bounding box for the text was modified
The first content proper heading "Welcome new hires who start this Summer!" starts as left aligned, but then shifts to center and therefore might be just a simple heading paragraph spacing change, though we can't be sure.
What we don't see here is a look at editing the custom theme, so we don't know all the additional settings added to this panel. As an active designer of new templates, I can't wait to dive into the changes.