Internet Explorer 10 uses 0 instead of 1 as the initial value for the flex-shrink
property. You have to manually set flex-shrink: 1
to each element, or assign a class. How can I automatically set it without assigning it manually or using a class?
You can always set a default rule in your stylesheet.
Use the universal selector to apply it to all elements.
* { flex-shrink: 1; }