While on a block setting page, I was clicking the navbar language menu selector to change into a new language, and got error: "A required parameter (sesskey) was missing"

Debug info:
Error code: missingparam
Stack trace:
line 496 of /lib/setuplib.php: moodle_exception thrown
line 567 of /lib/moodlelib.php: call to print_error()
line 73 of /lib/sessionlib.php: call to required_param()
line 84 of /lib/sessionlib.php: call to confirm_sesskey()
line 1370 of /lib/blocklib.php: call to require_sesskey()
line 1206 of /lib/blocklib.php: call to block_manager->process_url_edit()
line 1530 of /lib/pagelib.php: call to block_manager->process_url_actions()
line 960 of /lib/pagelib.php: call to moodle_page->starting_output()
line 1027 of /lib/outputrenderers.php: call to moodle_page->set_state()
line 164 of /my/index.php: call to core_renderer->header()

original page: https://qa.moodle.net/my/index.php?sesskey=k4YZ4g8P9e&bui_editid=40

Page with error after clicking any language: https://qa.moodle.net/my/index.php?bui_editid=40&lang=af