Twenty Fifteen: missing spaces for code standards.

Props Jayjdk, fixes #30076.


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Twenty Fifteen: Formatting cleanup for documentation, crossing eyes, dotting tees.

Props lancewillett, MikeHansenMe, fixes #30149.

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Add some docs to `wp.media.view.EditorUploader`.

Props ericlewis.
See #29951.

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Twenty Fifteen: adding licensing info for the image used in the screenshot.

Props sakinshrestha, fixes #30156.


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Twenty Fifteen: Use the new archive template tags and make archive template titling way simpler!

Props obenland, fixes #30246.


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Twenty Fifteen: use continue reading links for auto-generated excerpts to provide a readable link for screenreaders.

Props davidakennedy, kraftbj, fixes #30135.


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In `wp_insert_term()`, clean up accidental duplicate terms after insert.

In [30056], the UNIQUE index was removed from the 'slug' column of `wp_terms`.
While we have numerous checks in place to avoid the creation of unwanted
duplicate term+term_taxonomy pairs, it's possible that in certain edge cases -
such as during the lag caused by database replication, or a race condition
involving near-simultaneous creation of more than one term - we'll end up
unwittingly inserting two identical rows.

The current changeset minimizes this risk by introducing a failsafe mechanism
into `wp_insert_term()`. After a term and term_taxonomy are INSERTed, we check
to see whether the term just created is a duplicate of an existing term; if so,
we delete the new one and keep the old one. This prevents problems caused by
replication lag, because SELECT queries that take place after an INSERT will
hit the master database; it mitigates race conditions by enforcing that the
term that was created first (ie, the one with the lowest `term_id`) is
always the "canonical" one.

Props nacin, markjaquith.
See #22023, #5809.
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Enforce ORDER BY and LIMIT clauses in `term_exists()` queries.

In case of edge cases where a duplicate term might exist in a replicated
database for a split second, these explicit query clauses ensure that
`term_exists()` will always recognize the oldest matched term as the
canonical one. See [30238] for background.

Props pento.
See #22023, #5809.
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Do not create shared taxonomy terms.

A "shared" term occurs when two entries in the `wp_term_taxonomy` table share a
single `term_id`, and thereby correspond to the same row in `wp_terms`. This
changeset stops the practice of creating shared terms: each new row in
`wp_term_taxonomy` will receive its own row in `wp_terms`. The new strategy
for term creation depends on whether the installation's database schema is up
to date for 4.1:

* If so, terms are allowed to be created with the same slug as an existing term, as long as they are in different taxonomies and do not share a parent. Thus, a new tag with the slug 'wordpress' can exist alongside a category with the slug 'wordpress'.
* If not, new terms will be forced to have unique slugs. Thus, on an installation containing a category with the slug 'wordpress', a new tag 'WordPress' will get the slug 'wordpress-2'.

Fixes #21950. See #5809.
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