Markdown leads to null object reference

[mplsgrant]

⚠️ This issue respects the following points: ⚠️

• This is a bug. Not a question or feature request.
• The topic is not already reported at Issues. (I've searched it).
• Markor is up to date. See Releases for the latest version. Updates are available from F-Droid and GitHub.
• The bug is still present in the latest development version (git master). (Please download and try the test version of Markor, named Marder. Don't worry; Markor and Marder appear as completely separate applications. You can install both side-by-side, and Markor settings are not touched. In case the issue is resolved there, you don't need to create a bug report. The change will be part of the next Markor update.)

Description

I found that a certain combination of markdown leads to a null object reference in View mode.

Steps to reproduce

1. Open the Marder application.
2. Press the QuickNote button.
3. Paste the markdown seen below into the QuickNote screen.
4. Press the View mode button.
5. Observe the error seen below.

Markdown

- [ ] lorem
Ipsum

    Dolor

    Sit

Error

Please report at project issue tracker: java.lang.NullPointerException: Attempt to invoke virtual method 'int com.vladsch.flexmark.util.ast.Document.getLineNumber(int)' on a null object reference

Information

Android version: 16
Device: Pixel w/ Graphene
App Version: Marder as of 2025-12-31

Source

Something else (-> Additional info)

Format / File type

Markdown

Additional info / Log

-

[erik55]

Possible duplicate of #2718