How to limit first level comments in Praw Reddit?

Rather than using replace_more, just replace each MoreComments object as you get to it. This will prevent you from replacing any MoreComments objects that are not at the top level.

Below is a function that will iterate through top-level comments, replacing each MoreComments as it is encountered. This is inspired by example code from the PRAW documentation:

from praw.models import MoreComments

def iter_top_level(comments):
    for top_level_comment in comments:
        if isinstance(top_level_comment, MoreComments):
            yield from iter_top_level(top_level_comment.comments())
        else:
            yield top_level_comment

The way this generator works is that it yields top-level comments from the submission, but when it encounters a MoreComments object, it loads those comments and recursively calls itself. The recursive call is necessary because in large threads, each MoreComments object contains another top-level MoreComments object at the end.

Here's an example of how you could use it:

submission = reddit.submission('fgi5bd')
for comment in iter_top_level(submission.comments): 
    print(comment.author)