Align left problem

Hello

I just upgraded to 2.6 and am having a problem. Previously when inserting an image into a post I could click the image and click the left align icon which would make the image float to the left with the words to the right. However after the upgrade this no longer works. I have noticed that it is no longer inserting style=”float: left;” into the source and if I insert that into the source code manually the image is now where it should be floating on the left.

Can anyone help resolve this?