Tiddlywiki5: [BUG] Line breaks rendered incorrectly for Markdown tiddlers

[ifethereal]

Currently being addressed by #4684.

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Describe the bug
Line breaks are rendered incorrectly for Markdown tiddlers if breaks is false. That is, <br> appears when <br> is meant to be absent; <br> is absent when <br> is meant to be present.

To Reproduce
Steps to reproduce the behavior:

1. Go to the _MarkdownExample_ tiddler on the Markdown demo.
2. Note that the breaks setting is false for the Markdown plugin.
3. Observe the multiple <br> present in the _MarkdownExample_ tiddler by inspecting the source code of the page (although it can be noticed by eye too).
4. Add two spaces at the end of any line inside a regular plain-text paragraph of the _MarkdownExample_ tiddler which is not followed by a blank line.
5. Observe the disappearance of a <br>.

I have observed the same behaviour for Markdown tiddlers on my own TiddlyWiki (running on a Node.js server).

Expected behavior
Based on what I understand of the breaks setting for Remarkable, since breaks is false, there should have been no <br> within any one paragraph in the _MarkdownExample_ tiddler, and adding the two spaces should have introduced a <br>.

Screenshots
Using the preview pane to get everything on one screen. (There are two spaces after This page offers a brief overview of what it's like to use Markdown..)

Desktop (please complete the following information):

• OS: Windows 10
• Browser: Google Chrome 83.0.4103.61, Mozilla Firefox 76.0.1
• Version: TiddlyWiki 5.1.22

Additional context
N/A

[pmario]

I can confirm the issue. We will have a closer look.

[flibbles]

Weird how we found this issue separately in the same week.

[flibbles]

I probably should have just said I have PR fix standing by.

[saqimtiaz]

This was resolved in #4684 and be closed @flibbles @Jermolene

[Jermolene]

Thanks @saqimtiaz @flibbles