Yeah IDK. Wordpad is built around rich text, with all the weirdness and complexity that comes with it. I know for a fact that .rtf is absurdly complicated to work with, and I assume that .docx is similar.
I’m willing to bet that adding markdown to Notepad was a lot simpler than trying to make it work in Wordpad, especially since you’d probably still have to support rich text.
Both Wordpad and Win11-Notepad use the RichEdit control (which first appeared in Win95, brought to you by the Mail client group aka Capone - cuz no one else wanted to do a RichEdit text control). see https://devblogs.microsoft.com/math-in-office/windows-11-not... and https://learn.microsoft.com/en-us/cpp/mfc/rich-edit-control-...
The RichEdit control handles parsing RTF (I believe there was a CVE-level bug about RTF-handling in RichEdit - ahh - here we go https://www.kb.cert.org/vuls/id/368132/), the programmer/app is insulated from grokking RTF.
Here's sample code for opening an RTF file - https://learn.microsoft.com/en-us/windows/win32/controls/use...
Adding realtime conversion of text-only Markdown to the processed-richtext Markdown is slightly more difficult than an instant message-type edit control converting a text :) to a unicode emoji character representing :)
You'd have some bookkeeping to remember which lines are markdown and which are plain text. But it's not rocket science.
Imagine Win11-Notepad as WordPad with all the UI for rich text formatting disabled.
Hence why I use .txt and not .rtf (After having multiple RTF files become corrupted)
Syntax highlighting is definitely less complex than updating and rendering RTF and HTML.
There is configurable syntax highlighting in vscode.
Should an app like Notepad ever embed a WebView? (with e.g. tauri-apps/wry instead of CEF now FWIU)? Not even for a Markdown Preview feature IMHO.