Repoduction steps
Alternative 1
1) Browse to http://demos.telerik.com/aspnet-ajax/input/examples/overview/defaultcs.aspx
2) Click on Phone field -> whole field gets selected
3) Enter 'a' -> One time red flashing border and caret moves 1 position
4) Press 'a' again -> One time red flashing border and caret does not move

Alternative 2
1) Browse to http://demos.telerik.com/aspnet-ajax/input/examples/radmaskedtextbox/firstlook/defaultcs.aspx
2) Click on IP address field -> whole field gets selected
3) Enter 'a' -> Caret moves 1 position, no one time flash of border
4) Press 'a' again -> One time red flashing border and caret does not move

Expected behaviour at step 3 in both cases:
One time red flashing border and caret should be at first position

The PasswordStrengthChecker doesn't update if you right-click and paste using only the mouse.

<telerik:RadMaskedTextBox ID="txtCountryDigits" runat="server" SelectionOnFocus="CaretToBeginning" PromptChar="_" Width="50px" Mask="+###" ValidationExpression="+\d{1}.d{1}.d{1}" MaxLength="4" />
<telerik:RadMaskedTextBox ID="txtPhoneNumber" runat="server" SelectionOnFocus="CaretToBeginning" PromptChar="_" Width="116px" Mask = "(###) ###.####" ValidationExpression = "\(\d{3}\) \d{3}\.\d{4}" />
<telerik:RadMaskedTextBox ID="txtExtension" runat="server"  SelectionOnFocus="CaretToBeginning" PromptChar="_" Width="100px" Mask="x##########" MaxLength="11" />

This only affects the Edge browser as far as I can tell.

The Country Digits and Extension only allow one character to be entered when the MaxLength is set equal to the number of characters in the mask.  You can only enter 1 character if you tab into the control.  Click on the control with the cursor does not allow the entry of any digits.   Removing the MaxLength property allows entry of the full input.

The RadTextBox (and other input controls as appropriate) should have an aspx property to automatically trim leading & trailing whitespace from user input. This will help ensure that good quality data is passed to the database.

The only way this can currently be done is to custom code "mytextbox.Text.Trim();" for every control on the page, before the property is sent to the database.

  <telerik:RadNumericTextBox ID="RadNumericTextBox1" runat="server" 
MinValue="-999" MaxValue="999" NumberFormat-DecimalSeparator=","
    Type="Number" AllowOutOfRangeAutoCorrect="false" DataType="System.Decimal" NumberFormat-DecimalDigits="4"></telerik:RadNumericTextBox>

1) type in "12345,4321"

2) blur and the control give an error. The typed value became: "12345.4321"

3) The comma "," decimal separator is changed into dot "."

RadMaskedTextBox has a RequireCompleteText property that makes it a requirement that the full mask of the input be satisfied. The RadInputManager MaskedTextBoxSetting does not contain the same property. Please add this property with the same functionality to the MaskedTextBoxSetting.

If multiline textbox has set text that starts with break lines, on every postback one break line disappears form the text.

When RadText boxes have EnableAriaSupport=True and also have a tooltip set, the JAWS form fields dialog should list the control along with any text that might be in the textbox.
Currently it does not list the text.
see following support ticket for more details:  https://www.telerik.com/account/support-tickets/view-ticket?threadid=1081024

When setting client events in a RadTextBox and using an EmptyMessage, the EmptyMessage will trigger the event on page load.  This is true for a multiple TextMode but others are untested. 

When entering a letter in a DigitsOnly Masked textbox, the cursor is moved to the right instead of staying in the same place. 

Demo https://demos.telerik.com/aspnet-ajax/maskedtextbox/overview/defaultcs.aspx

Edge(wrong) - https://www.screencast.com/t/cYRBNxyKNs

Chrome(expected) - https://www.screencast.com/t/OcAxrVKPuYb8

P.S. when pressing 3 keys at the same time, the cursor goes to the end, it might be relevant to this issue

To reproduce the issue:

ASPX:

<telerik:RadTextBox ID="RadTextBox1" runat="server" MaxLength="1700" TextMode="MultiLine" Height="100px" Width="500px">
</telerik:RadTextBox>



Codebehind:

    protected void Page_Load(object sender, EventArgs e)
    {
        RadTextBox1.Text = @"aaaa aaaa aaaa aaaa aaaa aaaa aaaa bbbb aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa bbbb aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa ";
    }



Load the page, copy the text bbbb and paste it over some aaaa string. The cursor will go to the end and the contents scrolled to the bottom. See the attached video for more information.



The problem has been initially reported in this forum https://www.telerik.com/forums/ie11-radtextbox and recently in ticket #1153271.