• Fixed an XSS vulnerability in tooltip, collapse, and scrollspy plugins
• Improved how we query elements in our JavaScript plugins
• Inline SVGs now have the same vertical alignment as images
• Fixed issues with double transitions on carousels
• Added Edge and IE10-11 fallbacks to our floating labels example
• Various improvements to form controls, including disabled states on file inputs and unified focus styles for selects

Checkout the v4.1.2 ship list and GitHub project for the full details.