[TYPO3-english] core bug? can't delete endtime since update to 4.5 in several extensions eg. tt_news, dam, macina_banners

[carmen fröwis]

Hi List!

I've noticed that since the udate to 4.5.2 the end date for some extensions no
longer is erasable. these extensions configure the filed in the tca.php with
a lower-range:

        'endtime' => Array (
           ...
            'config' => Array (
               .....
                'range' => Array (
                    'upper' => mktime(0,0,0,12,31,2020),
                    'lower' => mktime(0,0,0,date('m')-1,date('d'),date('Y'))
                )
            )
        ),

without the lower range it works great. prior to 4.5 it went with the lower
range.
is this a core bug? or was it a bug before 4.5?
where one would have to report it?

greets carmen