That shouldn't normally happen. What field width do you have set on the table column variables? Anything other than x-large could be a problem.

Inputs have a minimum width in the Forms CSS, but when everything is read only (history, saved to repository, etc.) those inputs become div elements and they may no longer be protected by that.

I'd make sure your fields are set to x-large. If that doesn't work, try without any custom CSS at all because the read-only content may be affected by something that's not affecting the live form.

Worst-case scenario, you can override it with CSS like the following:

table .cf-field > div {
    width: 100% !important;
}