TYPO3 Core

Sure this is a duplicate? Same error message, but different solution and maybe a different reason?

Let's see if #76675 fixes this problem too. If not we can still re-open this issue here.

Working solution: Just delete the 3 rows from your template:
--------------
<f:layout name="Default" />

<f:section name="main">
...
</f:section>
--------------

if you don't use them and your template works without them.

Tested and works in Typo3 8.5.1 and DCE 1.5.2 (which was upgraded from 1.4.8 and this reason caused this issue)