2-character single-line does not display

Regardless of language/brush, entering a single line consisting of a 2-character string does not display on the frontend or in Preview.

The following do display correctly:

- Entries of 1 character and 3 characters
- 2/+ lines consisting of 2-character strings:


See also: https://a8c.slack.com/archives/C6GGX896G/p1659100898753839?thread_ts=1659085924.820659&cid=C6GGX896G

Reported in https://wordpress.org/support/topic/two-letters-text-doesnt-show/

Reproduce the reported cases in both the frontend and Preview: a single line with exactly two characters versus one- or three-character lines and multiple two-character lines. Trace the rendering path responsible for those views, then confirm that the two-character single-line case displays without regressing the working cases.

Written by the indexing model from the issue text.