Uncaught Exception: DateTimeZone::__construct():

[edent]

I tried manually using the Webmention Parsing Debugger tool.

I passed it a page which had previously sent me a WebMention:

wp-json/webmention/1.0/parse/?source=https%3A%2F%2Flunaticsproject.org%2F2023%2F10%2F01%2Fseptember-2023-summary%2F&target=https%3A%2F%2Fshkspr.mobi%2Fblog%2F2018%2F08%2Feasy-guide-to-building-mastodon-bots%2F&mode=aggregated&submit=Parse&_wpnonce=123456&_wp_http_referer=%2Fblog%2Fwp-admin%2Ftools.php%3Fpage%3Dwebmention-tools

I got this fatal error:

[06-Nov-2023 13:52:06 UTC] PHP Fatal error:  Uncaught Exception: DateTimeZone::__construct(): Unknown or bad timezone () in /shkspr.mobi/blog/wp-content/plugins/webmention/includes/Handler/class-wp.php:175
Stack trace:
#0 /shkspr.mobi/blog/wp-content/plugins/webmention/includes/Handler/class-wp.php(175): DateTimeZone->__construct()
#1 /shkspr.mobi/blog/wp-content/plugins/webmention/includes/Handler/class-wp.php(76): Webmention\Handler\WP->parse_site_json()
#2 /shkspr.mobi/blog/wp-content/plugins/webmention/includes/class-handler.php(84): Webmention\Handler\WP->parse()
#3 /shkspr.mobi/blog/wp-content/plugins/webmention/includes/class-tools.php(90): Webmention\Handler->parse_aggregated()
#4 /shkspr.mobi/blog/wp-includes/rest-api/class-wp-rest-server.php(1194): Webmention\Tools::read()
#5 /shkspr.mobi/blog/wp-includes/rest-api/class-wp-rest-server.php(1041): WP_REST_Server->respond_to_request()
#6 /shkspr.mobi/blog/wp-includes/rest-api/class-wp-rest-server.php(431): WP_REST_Server->dispatch()
#7 /shkspr.mobi/blog/wp-includes/rest-api.php(418): WP_REST_Server->serve_request()
#8 /shkspr.mobi/blog/wp-includes/class-wp-hook.php(310): rest_api_loaded()
#9 /shkspr.mobi/blog/wp-includes/class-wp-hook.php(334): WP_Hook->apply_filters()
#10 /shkspr.mobi/blog/wp-includes/plugin.php(565): WP_Hook->do_action()
#11 /shkspr.mobi/blog/wp-includes/class-wp.php(398): do_action_ref_array()
#12 /shkspr.mobi/blog/wp-includes/class-wp.php(779): WP->parse_request()
#13 /shkspr.mobi/blog/wp-includes/functions.php(1335): WP->main()
#14 /shkspr.mobi/blog/wp-blog-header.php(16): wp()
#15 /shkspr.mobi/blog/index.php(17): require('/...')
#16 {main}
  thrown in /shkspr.mobi/blog/wp-content/plugins/webmention/includes/Handler/class-wp.php on line 175