Type 'Program' can be sealed because it has no subtypes in its containing assembly and is not externally visible (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1852)

Dereference of a possibly null reference.

Dereference of a possibly null reference.

Dereference of a possibly null reference.

Possible null reference argument for parameter 'format' in 'bool CustomMainForm.ParseQFormatString(string format, out int integral, out int fractional)'.

Type 'AngleConverter' is a static holder type but is neither static nor NotInheritable (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1052)

If possible, make the underlying type of ButtonFlags System.Int32 instead of ushort (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1028)

Rename type name ButtonFlags so that it does not end in 'Flags' (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1711)

Do not declare visible instance fields (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1051)

Do not declare visible instance fields (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1051)