Getting a bunch of these errors after today's update to latest release:
[18-Sep-2018 16:13:23 UTC] PHP Fatal error: Undefined class constant 'CALLBACK_SAVE_VIEWS_PAGE_BUILDERS_FRONTEND_CONTENT_SETTINGS' in /wp-content/plugins/wp-views/inc/wpv-settings-screen.class.php on line 109
[18-Sep-2018 16:13:23 UTC] PHP Stack trace:
[18-Sep-2018 16:13:23 UTC] PHP 1. {main}() /wp-admin/admin-ajax.php:0
[18-Sep-2018 16:13:23 UTC] PHP 2. require_once() /wp-admin/admin-ajax.php:22
[18-Sep-2018 16:13:23 UTC] PHP 3. require_once() /wp-load.php:37
[18-Sep-2018 16:13:23 UTC] PHP 4. require_once() /wp-config.php:132
[18-Sep-2018 16:13:23 UTC] PHP 5. do_action($tag = *uninitialized*, $arg = *uninitialized*) /wp-settings.php:450
[18-Sep-2018 16:13:23 UTC] PHP 6. WP_Hook->do_action($args = *uninitialized*) /wp-includes/plugin.php:453
[18-Sep-2018 16:13:23 UTC] PHP 7. WP_Hook->apply_filters($value = *uninitialized*, $args = *uninitialized*) /wp-includes/class-wp-hook.php:310
[18-Sep-2018 16:13:23 UTC] PHP 8. call_user_func_array:{/wp-includes/class-wp-hook.php:286}(*uninitialized*, *uninitialized*) /wp-includes/class-wp-hook.php:286
[18-Sep-2018 16:13:23 UTC] PHP 9. WPV_Settings_Screen->init(*uninitialized*) /wp-includes/class-wp-hook.php:286
[18-Sep-2018 16:13:29 UTC] PHP Fatal error: Undefined class constant 'CALLBACK_SAVE_VIEWS_PAGE_BUILDERS_FRONTEND_CONTENT_SETTINGS' in /wp-content/plugins/wp-views/inc/wpv-settings-screen.class.php on line 109
After I manually added the constant (an empty string) just to make the errors hopefully stop, a different one happened, then another different one, etc.
This all happened while importing using https://wordpress.org/plugins/all-in-one-wp-migration/
I think the issue is that the plugin architecture must have changed quite a bit and, in the future, I should update my plugins and themes on Site B (importing to) before importing the export from Site A (source site where I did plugin updates before exporting).
So you can disregard this as I'm no longer seeing the issue after the import was done in this other way (update everything in both sites before export/import).