When concatenating or appending raws, the final raw object contains annotations with correct onsets but without the extras list associated with the annotations.
raw_2.annotations.append([1.0], [1.0], 'stim', extras=[dict(response=1, react_time=0.5)]
raw.append([raw_2])
print(raw.annotations) # => annotations 1 segment 'stim'
print(raw.annotations.extras) # => [{}]
It seems the issue lies in annotations.py/_combine_annotations function where it doesn't handle the extras between the two annots objects and construct the new returned object without the extras keyword argument.
When concatenating or appending raws, the final raw object contains annotations with correct onsets but without the extras list associated with the annotations.
It seems the issue lies in annotations.py/_combine_annotations function where it doesn't handle the extras between the two annots objects and construct the new returned object without the extras keyword argument.