Rhino Text Generation Bug

RhinoTextBugReport.cs

/// <summary>
/// Repro for intermittent failure of TextEntity.CreateExtrusions
/// The issue also affects TextEntity.CreateSurfaces
///
/// Expected Output:
///   - "ABCDEFGHIJKLMNOPQRSTUVWXYZ-0123456789" rendered on every line
///   
/// Actual Output:
///   - About 50% of the lines are truncated abd only print part of the string because the generated extrusion is null. 
///    e.g. "ABCDEFGHIJ"
/// 
/// Rhino Version 6 SR27 (6.27.20176.5001, 24/06/2020)
/// </summary>
public static void RhinoTextBugReport()
{
    for (var row = 0; row < 20; row++)
    {
        // text size
        var textHeight = 1;

        // font
        var font = Font.InstalledFonts().FirstOrDefault(o => o.EnglishFamilyName == "Arial" && o.Bold);

        var plane = Rhino.Geometry.Plane.WorldXY;
        plane.OriginY = 2 * row * textHeight;

        // text entity
        var entity = new TextEntity()
        {
            PlainText = "ABCDEFGHIJKLMNOPQRSTUVWXYZ-0123456789",
            Plane = plane
        };

        // dimension style for rendering
        var dimStyle = new DimensionStyle
        {
            Font = font,
            TextHorizontalAlignment = TextHorizontalAlignment.Left,
            TextVerticalAlignment = TextVerticalAlignment.Middle,
            TextHeight = textHeight
        };

        // this is the call that fails
        var extrusions = entity.CreateExtrusions(dimStyle, 2);

        // add to doc
        var doc = Rhino.RhinoDoc.ActiveDoc;
        foreach (var item in extrusions)
        {
            // sometimes the extrusions in the array are null, but not always
            if(item != null)
            {
                doc.Objects.AddExtrusion(item);
            }
            
        }
    }
}