[POSSIBLE BUG] WARNING!!! Thousands of transients in database

Hi!
I updated nextgen to the latest version and after a few hours I tried to export my database and I noticed that it has more than 28000 lines more than before. I investigated a little and I noticed that there are 28000 transients in wp_options table.
I tried to track down the problem, checked my theme files and couldn’t find the problem. Deactivated NextGen Gallery and transients were not created anymore. Everytime the ImageBrowser is loaded (not sure about the other views since I don’t use them) 2 transients are created. One containing all the content that ImageBrowser outputted looking like this (I censored it with ****VALUE****):
option name: _transient_e6f0fa886773f27c4d0e23c9b2e64d3f

<div class='ngg-imagebrowser' id='ngg-imagebrowser-ece1c6a875a1e4b9ec110ef93391ad5b-7618' data-nextgen-gallery-id="ece1c6a875a1e4b9ec110ef93391ad5b">
	<h4>********POST TITLE***************	</h4>

		<div id="ngg-image-0" class="pic" >
        <a href='**********IMAGE URL******************'
           title='***********ALT TEXT******************'
           data-src="*******IMAGE URL******************"
           data-thumbnail="********THUMBNAIL IMAGE URL*********"
           data-image-id="16379"
           data-title="*******IMAGE TITLE************"
           data-description="********IMAGE DESCRIPTION**********"
           class="shutterset_ece1c6a875a1e4b9ec110ef93391ad5b">
            <img title='*********IMAGE TITLE************'
                 alt='****************ALT TEXT***********'
                 src='**************IMAGE URL***********'/>
        </a>
	  </div> 

    <div class='ngg-imagebrowser-nav'>

        <div class='back'>
            <a class='ngg-browser-prev'
               id='ngg-prev-16380'
               href='****PREVIOUS IMAGE URL************; Back            </a>
        </div>

        <div class='next'>
            <a class='ngg-browser-next'
               id='ngg-next-16378'
               href='********NEXT IMAGE URL************'>
                Next                ►
            </a>
        </div>

        <div class='counter'>
            Picture 16 of 40        </div>

        <div class='ngg-imagebrowser-desc'>
            <p>
                *******IMAGE DESCRIPTION**********            </p>
        </div>

    </div>

</div>
<script type='text/javascript'>
	jQuery(function($) {
		new NggPaginatedGallery('ece1c6a875a1e4b9ec110ef93391ad5b', '.ngg-imagebrowser');
	});
</script>

and the other is just a transient_timeout.
Is this creating of transients a “normal” NextGEN Gallery behavior?
It really is a problem to me because I get thousands of views every day and my database grows some 40MB every day..

https://www.ads-software.com/plugins/nextgen-gallery/