When adding an instance of the module, clicking 'Add a New Tab' button:

Invalid array parameter detected in required_param(): optionid

line 599 of \lib\moodlelib.php: call to debugging()
line 32 of \mod\tab\mod_form.php: call to optional_param()
line 194 of \lib\formslib.php: call to mod_tab_mod_form->definition()
line 71 of \course\moodleform_mod.php: call to moodleform->moodleform()
line 260 of \course\modedit.php: call to moodleform_mod->moodleform_mod()