SSMS (19.3) crashes after using SQL Prompt (11.3.8) for a while to edit a sql script

Here is the exception in the windows event log:

Application: Ssms.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: System.Runtime.InteropServices.ExternalException
  at System.Drawing.Graphics.CheckErrorStatus(Int32)
  at System.Drawing.Graphics.DrawLine(System.Drawing.Pen, Int32, Int32, Int32, Int32)
  at RedGate.SqlPrompt.CommonUI.Forms.SchemaInformation.ObjectDefinitionBox.toolbar1_Paint(System.Object, System.Windows.Forms.PaintEventArgs)
  at System.Windows.Forms.Control.OnPaint(System.Windows.Forms.PaintEventArgs)
  at System.Windows.Forms.Control.PaintWithErrorHandling(System.Windows.Forms.PaintEventArgs, Int16)
  at System.Windows.Forms.Control.WmPaint(System.Windows.Forms.Message ByRef)
  at System.Windows.Forms.Control.WndProc(System.Windows.Forms.Message ByRef)
  at System.Windows.Forms.ScrollableControl.WndProc(System.Windows.Forms.Message ByRef)
  at System.Windows.Forms.Control+ControlNativeWindow.OnMessage(System.Windows.Forms.Message ByRef)
  at System.Windows.Forms.Control+ControlNativeWindow.WndProc(System.Windows.Forms.Message ByRef)
  at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr, Int32, IntPtr, IntPtr)

It is not the first time it happens. I have been coding for about 2 hrs.

Sql Prompt version: 11.3.8.22342

Ssms version: 

SQL Server Management Studio                        19.3.4.0
SQL Server Management Objects (SMO)                        16.200.48053.0+08fe64c9e8eb5ff3c7ea5787f145e9ecb3d57df8
Microsoft T-SQL Parser                        17.0.27.0+b6df00d03710e3fafcbe827aad08bdbe9d45d1ab
Microsoft Analysis Services Client Tools                        16.0.20054.0
Microsoft Data Access Components (MDAC)                        10.0.14393.8592
Microsoft MSXML                        3.0 6.0 
Microsoft .NET Framework                        4.0.30319.42000
Operating System                        10.0.14393