This task is a follow-up of {T190804}.
https://en.wikipedia.org/wiki/Wikipedia:Page_name#Technical_restrictions_and_limitations
**(1)** Are we going to catch the titles with characters that are silently dropped?
e.g. `:Mavetuna` will be published as `Mavetuna` (the colon is dropped, according to the following restriction:
>A pagename cannot begin with a colon :.
{F22117596}
**(2)** Although `#` is a invalid character, it's allowed in translated page titles in cx-testing. Even more, having `#` in the page title will make other invalid chars "valid", so a page title like ` # < > [ ] | { } _` seems to be valid in cx2-testing.
(3) "H#e|ge|||||||||||||||||" (no quotes) also seems to be valid and redirects to http://cx2-testing.wmflabs.org/index.php/H#e.7Cge.7C.7C.7C.7C.7C.7C.7C.7C.7C.7C.7C.7C.7C.7C.7C.7C.7C (discarding all characters after H):
{F22116895}
(4) Not all errors are communicated clearly to a user - in the screenshot the error message appears, but there are no details in the side panel. In the screenshot, the focus is on the invalid title, but no side panel error is displayed.
{F22653972}
(5) The documentation pages needs to be updated - https://en.wikipedia.org/wiki/Wikipedia:Page_name#Technical_restrictions_and_limitations and https://meta.wikimedia.org/wiki/Help:Page_name#Restrictions have slightly different list of restricted characters that are not allowed in the page title.