Problem using H in Emacs

Describe the bug
With some hacking I managed to get H to start in GNU Emacs, but the output is
buffered, so not seen. A typical session in Emacs looks like this
x = [r|sqrt(1:5)|]
p x

:t x
x :: MonadR m => ...

So the output from the type query appears, but the output from the p command does not.
If the program is now terminated with Ctrl-C the lost output of the p command appears, so
it was clearly buffered when it shouldn't be.

To Reproduce
Under Windows, I put the following in .ghci
set -fno-ghci-sandbox
:set -XDataKinds
:set -XGADTs
:set -XPartialTypeSignatures
:set -XOverloadedLists
:set -XQuasiQuotes
:set -XScopedTypeVariables
:set -XTemplateHaskell
:set -XViewPatterns

:set -i/w/dev/github/HaskellR/H/.stack-work/dist/8a54c84f/build/H/autogen

The last set is needed to prevent Paths_H autogen module from not
being found.

Now cd to HaskellR, run some trivial command to get Emacs Haskell
mode to start, and type into Haskell mote prompte:

:m +Language.R.Instance
:m +H.Prelude.Interactive as H.Prelude

initialize defaultConfig

Expected behavior
H mode should work like ghci mode with extra features for R.

Environment

• Windows 11
• 1.0.0 of HaskellR

Additional context
Initially I tried using this in .emacs.d/init.el:
(setq haskell-program-name "stack exec H")

This didn't work, perhaps because none of the
expected output was reaching the terminal
because of buffering.