Known Issue: ArcGIS Online Feature Writer - older workspaces opened in FME 2022.0 or newer have their parameters reset

Symptom

Opening a workspace (created in FME 2021.x or older) in FME 2022.0 or newer results in some of the ArcGIS Online FeatureWriter parameters being reset to their default values. Please note that this only affects the ArcGIS Online FeatureWriter, and does not affect the normal ArcGIS Online Reader.

Running the workspace as is will still run it with the original parameters, but visually the parameters show up different than expected. Going into the FeatureWriter parameters and clicking okay results in the parameters being changed, affecting any future workspace runs. 
 

Cause

The metafile behind the ArcGIS Online format changed, and in this change the parameter name for argisonline_mode changed to fme_feature_operation.
Due to the rename, the old values were not preserved, thus when opening an old workspace in a newer version of FME, the FeatureWriter does an implicit 'upgrade writer' when it is opened, causing the parameters to change.

For example, the value saved in the FeatureWriter in FME 2021.2 was arcgisonline_mode = UPDATE. Now, opening that same workspace in FME 2022.0, the parameters have reset to the defaults because the arcgisonline_mode parameter no longer exists in the metafile since it has been renamed to fme_feature_operation.
 

Resolution

Upon opening the workspace in FME 2022.0 or newer, update the FeatureWriter settings and from that point on it the parameters will be preserved.