Flush stdin after writing to a pager

[tucked]

I would love to see text immediately in this toy example:

import click
import os
import time

def _generator():
    for i in range(10000):
        time.sleep(0.01)
        yield f"{i+1:07}\n"

@click.command
def main():
    os.environ.setdefault("LESS", "-XFR")
    click.echo_via_pager(_generator())

main()

As it is currently, nothing will show until 512 lines have been yielded.
I suspect a flush after this line would do the trick:

click/src/click/_termui_impl.py

Line 468 in cdab890

c.stdin.write(text)

Related: #2542 ☹️

[G1DO]

Hey, I'd like to take a shot at this if no one else is working on it!