This avoids a (somewhat) costly lookup operation involving Contexts comparison. It aims to be effective on the basis that lookup calls within the same period of time are likely to target the same context (and therefore have the same result).
Caffeine seems to just fallback to a ConcurrentHashMap based implementation in this case anyway.
This fixes the issue Multicraft panels have with displaying ? characters in console. (absolute quality)
Related to: lucko/ExtraContexts#4
thanks @kashike
Continues from 3c773e6823 & #1210
3c773e6823