Arch Linux

Description:
The current version of retext fails to render a Markdown document when the webkit renderer is selected.

Additional info:
* package version(s): community/retext 7.2.2-2, extra/qt5-webkit 5.212.0alpha4-11

Steps to reproduce:
1. Open retext
2. Enable the live preview (<Ctrl><L>) if not done already
3. Switch on the Webkit renderer (Checkbox under Edit menu)
4. Create a dummy document with two lines (aka one empty line

This results in the following error message on the console for me.
```
Traceback (most recent call last):
File "/usr/lib/python3.10/site-packages/ReText/syncscroll.py", line 68, in _handlePreviewResized
self._updatePreviewScrollPosition()
File "/usr/lib/python3.10/site-packages/ReText/syncscroll.py", line 137, in _updatePreviewScrollPosition
pos.setY(preview_scroll_offset)
TypeError: setY(self, int): argument 1 has unexpected type 'float'
Process Process-1:
Traceback (most recent call last):
File "/usr/lib/python3.10/multiprocessing/process.py", line 315, in _bootstrap
self.run()
File "/usr/lib/python3.10/multiprocessing/process.py", line 108, in run
self._target(*self._args, **self._kwargs)
File "/usr/lib/python3.10/site-packages/ReText/converterprocess.py", line 72, in _converter_process_func
job = receiveObject(conn_child)
File "/usr/lib/python3.10/site-packages/ReText/converterprocess.py", line 41, in receiveObject
sizeBuf = recvall(sock, 4)
File "/usr/lib/python3.10/site-packages/ReText/converterprocess.py", line 34, in recvall
raise EOFError('Received 0 bytes from socket while more bytes were expected. Did the sender process exit unexpectedly?')
EOFError: Received 0 bytes from socket while more bytes were expected. Did the sender process exit unexpectedly?
Abgebrochen (Speicherabzug geschrieben)
```