Add an IG parameter opt in or out of the "Highlight text changes" check box.

[Healthedata1]

Based on this Zulip chat #IG creation > Opt out of the templates "Highlight text changes" text box

The "Highlight text changes" checkbox is always visible, even when there are no changes to highlight, which can be confusing and distracting for users.

Proposal:

Make this feature optional. Create a new ig parameter that lets editors enable or disable it.

[lmckenzi]

Checkbox should only show up if there's a new-content or modified-content class on the page. Lloyd will follow up to see what's going on with Eric's IG.