A preview that fails the captcha or the form token keeps no image. A session keeps one image, the directory has a size limit, and abandoned images go at the next upload.
A new editor needs a username and a password of at least 12 characters. A persistent login needs an unexpired key and an existing account. Removing an account revokes its persistent logins, and its sessions end.
Same-site redirects are now relative paths, and a saved page on another site is ignored. The HTTP to HTTPS redirect takes its host from the new SITE_URL setting, and without it the pages refuse plain HTTP.
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