Update to 1.11.16 broke admin interface

We are running WP on Nginx at Swedish web host Loopia (https://loopia.se). When I installed the latest update of BLC, the admin interface broke down and it was no longer possible to log in. Reverting to 1.11.15 fixed the problem.

Our dev/test site runs on Apache, also at Loopia, and the upgrade did not cause any problems at all there.

WP: 5.8.1
PHP: 7.4.21
Avada theme: 7.4.2

… and 28 other plugins besides BLC.

### Active Plugins (29) ###

Ivory Search: by Ivory Search
Akismet Anti-Spam: by Automattic
Archivist - Custom Archive Templates: by Eric Teubert
Broken Link Checker: by WPMU DEV
Classic Editor: by WordPress Contributors
Contact Form 7: by Takayuki Miyoshi
Disable URL Autocorrect Guessing: by Hauke Pribnow
Yoast Duplicate Post: by Enrico Battocchi & Team Yoast
Google Tag Manager for WordPress: by Thomas Geiger
Flamingo: by Takayuki Miyoshi
Avada Builder: by ThemeFusion
Avada Core: by ThemeFusion
Google XML Sitemaps: by Auctollo
Google Universal Analytics: by Audrius Dobilinskas
Insert Headers and Footers: by WPBeginner
List all URLs: by Evan Scheingross
Listo: by Takayuki Miyoshi
Login Logo: by Mark Jaquith
Post Type Switcher: by Triple J Software
Inc.
Public Post Preview: by Dominik Schilling
Really Simple SSL: by Really Simple Plugins
Redirection: by John Godley
Regenerate Thumbnails: by Alex Mills (Viper007Bond)
Slider Revolution: by ThemePunch
GDPR Cookie Consent Banner: by termly
Wordfence Security: by Wordfence
Yoast SEO: by Team Yoast
Asset CleanUp: Page Speed Booster: by Gabe Livan
WP Super Cache: by Automattic

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