"Start a discussion" button is cutted

[InfoLibre]

When you show tags on 3 colomns instead of two (on a large screen), the "Start a discussion" button is cut at its right side.

[InfoLibre]

The size of the button is correct when I uncheck "width 100%" :

[dcsjapan]

The "Log In to Reply" button seems to be affected by a similar issue:

http://discuss.flarum.org/d/672-polish-language-extension/11

[ghost]

For information, the Send Password Reset Email button is also affected (especially when it's translated Envoyer le courriel de réinitialisation du mot de passe in French, I should probably reduce it!).