Reconsider x boundaries of histograms.

[carrascomj]

To make it fully comparable across reactions at a glance, the histograms should have the same domain. If not, one has to look at the values drawn in the axis, which is not that good for publishing since the numbers are very small.

We need to decide between:

• the histograms of a side share the domain;
• make it configurable (requires some x-scaling wrangling again); or
• leave as is since the global scale may not allow to see anything at all.

[carrascomj]

Another alternative from @NicholasCowie:

Maybe just indicate with a bar the medium point across a variable (side).

That is a good compromise to tackle the small-and-large visualization.