Stale element exception happen when properties of element on which your script is trying to perform some operation is changed. If you want to click a span with text "XXX" you can directly click on that:
WebDriverWait(driver, 20).until(EC.presence_of_element_located((By.XPATH, "//a[span[text()='XXX']]")))
If your requirement is to loop trough all such elements then:
connections=driver.find_elements_by_css_selector("a span[class='mn-connection-card__name t-16 t-black t-bold']")
print(len(connections))
for i in range(len(connections)):
connections=driver.find_elements_by_css_selector("a span[class='mn-connection-card__name t-16 t-black t-bold']") #Created Fresh element list, so it wont be stale
if connections[i].text == "XXX"
connections[i].click
break