I'm upgrading an app from rails 5.2 to 6.1.7, as well as upgrading ruby from 2.6.10 to 3.0.5. Now all of the <%= render "partial_name" %> blocks in the erb view files are broken and throwing the error undefined method safe_append= for {:add_to_stack=>true}:Hash with the hint: safe_append= is being called on a add_to_stack object, which might not be the type of object you were expecting. This appears to be a deprecated ActionView::StreamingBuffer method. I did ensure that actionview has also been updated to 6.1.7, and I'm also not seeing any streaming buffer breaking changes in Rails 6 or 6.1. I don't see any related issues online anywhere. Anyone know what could be causing this?
To officially answer my own question, this seems to have been too large of an upgrade to undertake. I broke this task up into smaller pieces and first upgraded to ruby 2.7.7 and rails 6.0.6.1 and was able to get things going.