Auto-reveal "re:" content warnings in replies

[dwminer]

Is your feature request related to a problem? Please describe.
I really like the feature "auto-reveal equal CWs in replies" that Megalodon offers. However, many Mastodon clients automatically prepend the CW with "re:", "RE:" or similar when replying, which causes those replies to remain collapsed even with this setting on.

Describe the solution you'd like
It would be helpful if Megalodon could also automatically reveal replies with these "reply" CWs. I think the safest way would be to have a hard-coded list of known prefixes that could be tested against, possibly in a case-insensitive manner.

Describe alternatives you've considered
Another alternative would be to have an option to auto-reveal all CWs in replies, or any CW that includes the original parent CW, but I would personally find this too broad and be less likely to use it.