PDFsharp & MigraDoc Foundation

Hiya!

I recently ported over from the framework to the core version of PdfSharp-Migradoc-WPF and I was getting this exception.

After diving into the PdfSharp repo, I did find out what was going wrong in the GetMinMergedCell method.
I was trying to merge cells down into a row that didn't exist yet, and upon fixing that it was creating the pdfs again.

I am just suggesting if you all could change this exception message to something with more information so that others can fix this error if they run into it?

Thanks!

Attempted to merge cells into a non-existent row. Please ensure the row exists before merging cells into it to avoid this issue.

If you believe that enhancing the exception message in PdfSharp-Migradoc-WPF could benefit other users and help them in resolving similar errors, I recommend reaching out to the library's maintainers or contributing to the project's GitHub repository. By submitting a feature request or opening an issue, you can provide your valuable feedback and suggestions to the developers, who can consider incorporating it into future updates or releases of the library. Flappy Bird