When opening, closing and editing Visual Studio documents, tabs change positions to be always visible in minimum number or rows. And the more tabs change positions and rows, the more our workspace becomes disorganized. I’ve created the new Stable tabs layout that reduces excessive tab movements:

Stable tabs layout option
While previous layouts were just wrappers around standard WPF panels, the Stable layout is implemented completely in Tabs Studio and provides ample potential opportunities for customization. The most noticeable visual distinction of the new layout is not justified last row. It doesn’t add stability, but I think is more visually pleasant:

All tab rows justified except the last one
The first actual stability feature is RowBuffer. RowBuffer is space reserved on each tab row that keeps tabs on their positions when some of them slightly increase width. For example, default 30 pixels of RowBuffer can absorb additional width of a close tab button when you switch to this row and 3 document modification asterisks.
You can adjust the RowBuffer value with the following style:
<Style TargetType="TabsStudio:Tabs" BasedOn="{StaticResource DefaultTabsStyle}">
<Setter Property="RowBuffer" Value="20"/>
</Style>
Another stability feature keeps tabs on their positions when some of them become shorter. When it is possible to reduce number of rows due to shorter tabs, a new arrangement is delayed until the next major relocation.
Events that trigger major relocation are tab creation, tab removal, window size change. Events that don’t lead to tab rearrangement (within limits of RowBuffer) are tab selection, document modification, tab extension creation or removal.
For a new Tabs Studio installation Stable is the default layout now. I’m thinking about removing Standard and Wrap layouts in the future.
Download link: Tabs Studio v2.3.6.