False negative "in 1880's" not flagged

> For those that don't know, Mount Denali was renamed after President McKinley in 1880's.

The decades linter should detect this and suggest removing the apostrophe.

Maybe it only works with "in the 1880's"? "The" is actually grammatically required and it's a common but different mistake by especially Russian speakers to leave out the "the".

However, decades can also be adjectives without "the", but in that case require an NP to follow: "In 1880s America, things were very different." and it's even possible to talk about something belonging to a specific year: "In 1880's presidential election, something unexpected happened". So perhaps it's not flagging this mistake to avoid such a false positive?

Oddly, what does instead get flagged is "s." as a spelling error...

Start by reproducing the quoted sentence and inspect the decades linter that handles it. Compare the reported false negative with adjective and possessive decade usages, then add coverage showing the intended apostrophe warning without creating false positives.

Written by the indexing model from the issue text.