Currently the Css selector for the Adding CSS rule chain page is over 3000px wide.

I've tested this in both Seven and Adminimal themes. I've solved this problem by using themekey to apply some css to the admin pages that limits the selection box to a max width of 400px. Clearly this is a minor issue but I thought I'd post my solution at least to help out anyone else having the issue. I'm using the Adminimal theme and it provides a custom css file in the files directory called "adminimal-custom.css" I added the following

.themekey-property-theme, .themekey-property-property, .themekey-fadeable, .form-select{
  max-width: 400px;
}

CommentFileSizeAuthor
select-box-2.png87.99 KBbigmonmulgrew
select-box.png65.72 KBbigmonmulgrew
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