Why do my horizontal toolstrips keep stacking verticaly?

I'm using a ToolStripContainer that contains three ToolStrips. At design time I move the ToolStrips to the positions I want them in, which is in a horizontal row across the top of the form like this:

I then close and save the Form. However, if I open the form up again the ToolStrips end up stacked up on the left side of th开发者_StackOverflowe ToolStripContainer like this:

How can I keep the ToolStrips in the positions that I specify?

This is a bug with Visual Studio. I've had the same issues for years. The only way I've found is to programmatically set all the ToolStrips' Dock property to Right. Do this in the Form's constructor, just after the call to InitializeComponent.