iframe embed filter value starting with # not working

[rajiv2]

We are constructing embed urls for our iframe along with all the filter values. All the filters work fine except when the filter value starts with a hash (#). We have instances where certain filter values start with # (ex: #firstName). Looker is not picking up and not populating the filters with this value. Rest of the filter values without the hash works fine. Any ideas on how this can be resolved?