It seems something with the configuration of Notepad++ 7.95 causes issues with MarkDown support (Which is out of the box).
In order to reproduce:
1. Install Notepad++ 7.95 PortableApps. Make sure it is a clean installation, not an update of previous version.
2. Run Notepad++.
3. Open a MarkDown document (*.md).
4. See there is no syntax highlight.
Compare that to:
1. Download Notepad++ 7.95 Portable from the official site (https://notepad-plus-plus.org/downloads/).
2. Unzip the folder.
3. Run Notepad++.
4. Open a MarkDown document. You'll see the syntax highlight (Out of the box support).
P. S.
It might happen on an update as wall, need to check.