Simplified bridge cards prevent censored users from modifying built-in bridges

A forum user has reported that the new, simplified bridge card format developed for built-in bridges in Tor Browser 13.5 has broken a workflow used by some censored users to modify built-in bridges. The example given is changing the domain front, in the case that the domain front is blocked in the censored country – e.g. https://github.com/net4people/bbs/issues/197. The same user also mentions the need to "backup the default bridges for legit reasons".

The exact workaround may be a little hacky. Is this a supported use case? Are there any risks in allowing users to effectively modify built-in bridge lines, and should we be encouraging users to copy complete bridge lines from official channels instead?