Need a way to add words with numbers to learned words

I'll look into it. There should probably also be words with -

Does anything else come to mind, what other characters should we take into?

Things like below

Numbers
3D
4K
5G
2FA
3M

Hyphen
well-being
state-of-the-art
mother-in-law
check-in
long-term

Underscore
user_name
first_name
file_path
data_value
home_address

Other characters
C++
C#
AT&T
R&D
Q&A

I think we can start with

Numbers

-

_

&

looking into this properly now. the learned-words filter is deliberately narrow at the moment so it doesn't pick up junk (stray punctuation, random tokens), and I want to see what starts sneaking in once I widen it to numbers, - , _ and &. will add it right after 2.1.2 is out on the App Store.

turned out this overlapped with another request (portuguese hyphenated forms weren't sticking either, same root cause: the "-" was getting dropped before a word could be saved), so I just went ahead and did it now instead of waiting. it's in for build 407: words with - _ & and numbers now save as learned words, so well-being, user_name, AT&T, 3D, covid19 stick and start showing as predictions once you've typed them a few times. bare numbers (years, phone numbers) stay out on purpose. once 407 is up, give it a go and tell me if anything you'd expect to save still doesn't.