https://www.syncfusion.com/forums/31038/styleinfo-passwordchar-only-masks-the-password-text-users-can-still-copy-paste-to-notepad
StyleInfo.PasswordChar only masks th... | WinForms Forums | Syncfusion
Forum Thread - GridControl - StyleInfo.PasswordChar only masks the password text, users can still copy-paste to notepad and see the actual p...
masksthwinformsforumssyncfusion
https://learn.microsoft.com/ja-jp/dotnet/api/system.windows.forms.textbox.passwordchar?view=netframework-4.8.1&redirectedfrom=MSDN
TextBox.PasswordChar Property (System.Windows.Forms) | Microsoft Learn
Gets or sets the character used to mask characters of a password in a single-line TextBox control.
property systemwindows formstextboxmicrosoftlearn