Your work place has an online forum used by all employees and managers.
Your workplace also has a uniform policy.
A few employees (amongst hundreds) don't wear the standard uniform. It doesn't affect how they do their jobs.
One employee occasionally makes snotty and ignorant comments on the forum about some people not wearing correct uniform.
You know some of the employees have invisible disabilities and this can affect what they are able to wear. You also know these comments make them uncomfortable and sad. But no one ever responds.
Would you respond to these comments? Do these comments amount to indirect disability discrimination?