Sometimes we have formulas which are to long to fit inside `\textwidth`. Currently our authors need to rewrite them. We might look into a solution for automatically resizing them, in case they are too big. There ist for example the package `adjustbox`. The command \adjustbox{max width=0.8\textwidth}{<content>} would resize `<content>` when it is too wide (it works like `\resizebox` of `graphics). However, `<content>` will be in text mode. We could use \begin{adjustbox}{max width=0.9\textwidth} \begin{center} $\begin{aligned} ..... \end{aligned}$ \end{center} \end{adjustbox} But this wouldn't work together with `\allowdisplaybreaks`. There is also the package `resizegather` for automatically resizing the environment `gather`, but we need a package for the command `align*`.