cvonk

That was interesting. Disabled all plugins except a few to enforce roles. Changed the theme to Twenty Seventeen. Success.
Returned to Atahualpa 3.7.2 theme. Success.
Enabled the plugins in batches of 4. Success all the way up to the last plugin.
Puzzled, but happy I can import the .svg files again.

thanks,

Thanks. Will try. Meanwhile, the SVG file is
https://coertvonk.com/wp-content/shield/math-subtractor-fs-block.svg

/c

Thank you. Now I can access the settings page without a 500 error