When clicking with the right mouse-button on one of the system buttons, and then dragging the mouse over the button until leaving it, without releasing the mouse-button itself, the button stays marked. It is reproducible in all themes.

Workaround:

public Form1()
{
    InitializeComponent();
 
    this.radRibbonBar1.RibbonBarElement.RibbonCaption.MinimizeButton.MouseLeave += Button_MouseLeave;
    this.radRibbonBar1.RibbonBarElement.RibbonCaption.MaximizeButton.MouseLeave += Button_MouseLeave;
    this.radRibbonBar1.RibbonBarElement.RibbonCaption.CloseButton.MouseLeave += Button_MouseLeave;
}

private void Button_MouseLeave(object sender, EventArgs e)
{
    RadImageButtonElement btn = sender as RadImageButtonElement;
    if (btn != null)
    {
        btn.IsMouseDown = false;
    }
}

To reproduce:

Add a RadRibbonBar to a Form. Add a RadTextBox to the bottom of the Form. Start the application, click the textbox and press the alt key. You will see that the focus will be taken away. This does not allow you to input key combinations into RadTextBox, such as Alt + 457.


Workaround:

Use the following custom RadRibbonBar:

public class MyRadRibbonBar : RadRibbonBar
{
    protected override ComponentInputBehavior CreateBehavior()
    {
        return new MyRibbonBarInputBehavior(this);
    }


    public override string ThemeClassName
    {
        get
        {
            return typeof(RadRibbonBar).FullName;
        }
        set
        {
        }
    }
}


class MyRibbonBarInputBehavior : RadRibbonBar.RibbonBarInputBehavior
{
    public MyRibbonBarInputBehavior(RadRibbonBar owner)
        : base(owner)
    {
    }


    protected override bool SetInternalKeyMapFocus()
    {
        if ((this.Owner as RadRibbonBar).ContainsFocus)
        {
            return base.SetInternalKeyMapFocus();
        }


        return false;
    }
}

To reproduce:
1.Add a RadRibbonBar (with several groups and buttons inside a group) and a theme (i.e. TelerikMetro).
2.Apply the theme for the RadRibbonBar: setting the ThemeName property to "YourThemeName".
for example: this.radRibbonBar1.ThemeName = "TelerikMetro";
3. Run the application and resize the form in a way to collapse all ribbon groups. When you open the popup for the group, all popup elements are with incorrect style.

Workaround: load the theme in the form's constructor.

To reproduce:
1.Create a RadRibbonForm and add a QuickAccessToolBar and a Contextual Tab Group
2.Use the following code:
public Form1()
{
    InitializeComponent();

    this.AllowAero = false;
    radRibbonBar1.RibbonBarElement.IconPrimitive.Visibility = ElementVisibility.Visible;
    ThemeResolutionService.ApplicationThemeName = "TelerikMetro";
}
3.Run the application. Position the QuickAccessToolBar below the ribbon via the drop down menu. Note that the Contextual Tab Group is shifted to the right.

Workaround:
this.radRibbonBar1.QuickAccessToolBar.RadPropertyChanged += QuickAccessToolBar_RadPropertyChanged;

private void QuickAccessToolBar_RadPropertyChanged(object sender, Telerik.WinControls.RadPropertyChangedEventArgs e)
{
    if (e.Property.Name == "QuickAccessToolbarBelowRibbonProperty")
    {
        if (this.radRibbonBar1.RibbonBarElement.QuickAccessToolbarBelowRibbon == true)
        {
            this.radRibbonBar1.RibbonBarElement.RibbonCaption.Margin = new Padding(-15, 0, 0, 0); 
        }
        else
        {
            this.radRibbonBar1.RibbonBarElement.RibbonCaption.Margin = new Padding(0); 
        }
    }
}

Steps to reproduce:
1.Open the ThemeViewer and select a random theme (e.g. TelerikMetro)
2.Click the "Show Form" button, related to "ribbonbar & office 2007 app menu, status strip". As a result a RadRibbonForm is shown. Notice that it has a form icon and a QuickAccessToolBar.
3.Click on the arrow button in the QuickAccessToolBar and select "Show below the Ribbon".
Note that the BackColor behind the form's icon is not correct.

Workaround:
this.radRibbonBar1.QuickAccessToolBar.RadPropertyChanged += QuickAccessToolBar_RadPropertyChanged;

private void QuickAccessToolBar_RadPropertyChanged(object sender, Telerik.WinControls.RadPropertyChangedEventArgs e)
        {
            if (e.Property.Name == "QuickAccessToolbarBelowRibbonProperty")
            {
                if (this.radRibbonBar1.RibbonBarElement.QuickAccessToolbarBelowRibbon == true)
                {
                    this.radRibbonBar1.RibbonBarElement.RibbonCaption.Margin = new Padding(-15, 0, 0, 0); 
                }
                else
                {
                    this.radRibbonBar1.RibbonBarElement.RibbonCaption.Margin = new Padding(0); 
                }
            }
        }

Steps to reproduce:
1.Open the ThemeViewer and select a random theme (e.g. TelerikMetro)
2.Click the "Show Form" button, related to "ribbonbar & backstage view, status strip". As a result a RadRibbonForm is shown. Notice that it has a form icon and a QuickAccessToolBar.
3.Click on the arrow button in the QuickAccessToolBar and select "Show below the Ribbon".
Note that the BackColor behind the form's icon is not correct.

Workaround: this.radRibbonBar1.RibbonBarElement.CaptionFill.Margin = new Padding(-20, 0, 0, 0);

To reproduce:
- Add ribbon bar with a few buttons subscribe to ScreenTipNeeded event and show different text for each button.
- Collapse the tabs by clicking the collapse button, the expand a tab by clicking its name.
- You will notice that the ScreenTipNeeded event is not fired.

Workaround:
Create separate screen tip for each element:
RadOffice2007ScreenTipElement button2Tip = new RadOffice2007ScreenTipElement();
button2Tip.CaptionLabel.Text = "button 2";
button2Tip.MainTextLabel.Text = "button 2";

radButtonElement2.ScreenTip = button2Tip;

To reproduce:

Add a RadRibbonForm and set the theme to Office2013Light. Start the application and click the backstage button. Click the close button and you will see an exception.

Workaround:

this.RibbonBar.BackstageControl.BackstageElement.TitleBarElement.CloseButton.MouseDown += TitleBarElement_MouseDown;
void TitleBarElement_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
{
    this.RibbonBar.BackstageControl.BackstageElement.TitleBarElement.CanManageOwnerForm = false;
    this.Close();
}

To reproduce:  
1. Add WindowsForm and RadRibbonBar 
2. Use this code snippet 
this.Text = string.Empty;
this.ControlBox = false;
this.radRibbonBar1.Text = "Example"; 
3. Run the project and you will see that title is visible in the Form and in the RadRibbonBar

Workaround: Use RadForm or RadRibbonForm and set the Text property.
If you use the WindowsForm, please use this code snippet: 
this.ControlBox = false;
this.radRibbonBar1.Text = "Example";
this.FormBorderStyle = FormBorderStyle.None;

To reproduce:

Create a RadRibbonForm and set its ApplicationMenuStyle to BackstageView. Start the application open the backstage, click the maximize button and then again to set the Form back to normal. You will notice that the Form cannot be set back to normal.

Workaround:

Manually change the WindowState of the Form.

this.RibbonBar.BackstageControl.BackstageElement.TitleBarElement.MaximizeButton.MouseDown +=MaximizeButton_Click;

void MaximizeButton_Click(object sender, EventArgs e)
        {
            if (this.WindowState == FormWindowState.Maximized)
            {
                this.WindowState = FormWindowState.Normal;
            }
            else if (this.WindowState == FormWindowState.Normal)
            {
                this.WindowState = FormWindowState.Maximized;
            }
        }

To reproduce:
- Change the ApplicationMenuStyle to BackstageView.
- Add some tabs with different content.
- Start the application and change the tabs several times, you will notice that the content is not changed.

To reproduce: 
- add RadRibbonBar with several CommandTabs and private void Form1_Load(object sender, EventArgs e) { radRibbonBar1.Expanded = false; } 
- add RadButton and on its Click event use: private void radButton1_Click(object sender, EventArgs e) { radRibbonBar1.CommandTabs[0].Visibility = Telerik.WinControls.ElementVisibility.Collapsed; } 
As a result the CommandTab is collapsed but some empty space remains.

Workaround: private void radButton1_Click(object sender, EventArgs e) { radRibbonBar1.CommandTabs[0].Visibility = Telerik.WinControls.ElementVisibility.Collapsed; this.radRibbonBar1.Expanded = !this.radRibbonBar1.Expanded; this.radRibbonBar1.Expanded = !this.radRibbonBar1.Expanded; }

To reproduce:
- add RadRibbonbar with two groups;
- add several RadButtonsElements in each group;
- subscribe for the ToolTipTextNeeded event:

private void radRibbonBar1_ToolTipTextNeeded(object sender, ToolTipTextNeededEventArgs e)
{
    e.ToolTipText = sender.ToString();
}

If you hover a certain button, the tool tip for button element appears, which is correct. If you hover precisely the ribbon bar group, the correct tool tip also appears. But after that each element hovering, displays the wrong tool tip.

To reproduce:
-add RadRibbonBar (ControlDefault theme) and several tabs;
-click the ribbon bar arrow to collapse the ribbon bar;
-click the first tab to show the pop up;
-click the ribbon bar arrow once to expand the ribbon bar and click it again to collapse it;
-click the tab does not display it from the first time;

To reproduce: - add RadRibbonForm; - add one tab with RadToggleButtonElement; - subscribe to toggle button click event and use the following code: public Form1() { InitializeComponent(); RadOffice2007ScreenTipElement tip1 = new RadOffice2007ScreenTipElement(); tip1.CaptionLabel.Text = "Button1"; tip1.MainTextLabel.Text = "My Text"; RadOffice2007ScreenTipElement tip2 = new RadOffice2007ScreenTipElement(); tip2.CaptionLabel.Text = "Button2"; tip2.MainTextLabel.Text = "My Text"; radToggleButtonElement1.ScreenTip = tip1; } private void radToggleButtonElement1_Click(object sender, EventArgs e) { radRibbonBar1.Expanded = false; } When the screen is shown (hovering the toggle button), then click the button and the ribbon bar will collapse. As a result the screen tip will not disappear even on mouse move. 

Workaround: private void radToggleButtonElement1_Click(object sender, EventArgs e) { radRibbonBar1.Expanded = false; RadToggleButtonElement btn = sender as RadToggleButtonElement; if (btn != null && btn.ScreenTip != null) { PropertyInfo[] pinfos = ((ComponentBehavior)radRibbonBar1.Behavior).GetType().GetProperties(BindingFlags.NonPublic | BindingFlags.Instance); PropertyInfo barProperty = ((ComponentBehavior)radRibbonBar1.Behavior).GetType().GetProperty("ScreenPresenter", BindingFlags.NonPublic | BindingFlags.Instance); Form screenTip = barProperty.GetValue(((ComponentBehavior)radRibbonBar1.Behavior), null) as Form; screenTip.Hide(); } } 

To reproduce: Add a RadRibbonBar, add a ribbon tab with some groups and buttons. Run the application, autohide the content of the tabs, minimize the application, maximize it, open the tab the buttons are overlapping each other.

To reproduce: Add a RadRibbonBar, set it to backstage view, add a ribbon tab, run the application autohide the content of the tabs, you will notice that 2 pixels are cut off the BackstageView button

To reproduce:

Add a RadRibbonBar and a RibbonTab.
Add a control to the form (for example a textbox).
Subscribe to its LostFocus event and set the tab's visibility to collapsed in the event handler.
When you start the application click the textbox, then click the tab and you will see that the tab will hide but the content will stay visible.

To reproduce:
- add RadRibbonBar containing a Contextual tab group (composed of four tabs);
- add several RadRadioButton-s indicating which tab to be visible/collapsed:

private void radRadioButton1_ToggleStateChanged(object sender,
    Telerik.WinControls.UI.StateChangedEventArgs args)
{
    if (args.ToggleState == Telerik.WinControls.Enumerations.ToggleState.On)
    {
        this.ribbonTab1.Visibility = Telerik.WinControls.ElementVisibility.Visible;
    }
    else
    {
        this.ribbonTab1.Visibility = Telerik.WinControls.ElementVisibility.Collapsed;
    }
}

As a result, when some tab is collapsed, contextual tab group width is not changed.

======================
Workaround: set collapsed tab width to 0 and update ribbon captions's layout:

ribbonTab1.Visibility = Telerik.WinControls.ElementVisibility.Collapsed;
ribbonTab1.Size = new Size(0, this.ribbonTab1.Size.Height);

radRibbonBar1.RibbonBarElement.InvalidateMeasure(true);
radRibbonBar1.RibbonBarElement.UpdateLayout();
radRibbonBar1.RibbonBarElement.RibbonCaption.CaptionLayout.InvalidateMeasure(true);
radRibbonBar1.RibbonBarElement.RibbonCaption.CaptionLayout.UpdateLayout();

To reproduce: Add a ribbon bar with tabs and items inside. Press alt key and select some tab, in some tabs the children items KeyTIps will not appear.