The dropdown feature should try to adjust it's width with the largest text inside:
Current Release:
http://i.gyazo.com/5a651b4140790f6870a6dc26a3996609.png
What it should look like:
http://i.gyazo.com/f9918f592fff2cd421223f16d3d7dc5c.png
Please note that I've alredy found a solution:
style='width: auto !important;'
I'll make this into an option, but leave the other as default I think. Since Material design likes to have their dropdown matching width a lot of the times.
Added in 91985119ac10cce516ce5f28f10006748ebf17da
2017: constrainWidth is now passed as an object option/property upon jquery initialization of the dropdown. Check http://materializecss.com/dropdown.html !
sample (with hover, lol):
$(".dropdown-button").dropdown({ hover: true, constrainWidth: false });
Still not working in march 2018
@adhavalboy
If you go into materializecss.js and go to line 2199 you can change the default from true.

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Still not working in march 2018