mkay

####Manager:

System Settings > ckeditor > Remove plugins
remove stylescombo from the list

System Settings > ckeditor > CSS styles set
custom:/assets/styles.js

Filesystem:

mkay

<!-- DEBUG -->
<div style="position: fixed; z-index:999; bottom:0;">
    <span class="label label-default visible-xl-up hidden-lg-down">XL</span>
    <span class="label label-success visible-lg-up hidden-xl-up hidden-md-down">LG</span>
    <span class="label label-info visible-md-up hidden-lg-up hidden-sm-down">MD</span>
    <span class="label label-primary visible-sm-up hidden-md-up hidden-xs-down">SM</span>
    <span class="label label-warning visible-xs-up hidden-sm-up">XS</span>
</div>
<!-- /DEBUG -->

mkay

<!-- DEBUG -->
<div style="position: fixed; z-index:999; bottom:0;">
    <span class="badge badge-secondary d-none d-xl-block">XL</span>
    <span class="badge badge-secondary d-none d-lg-block d-xl-none">LG</span>
    <span class="badge badge-secondary d-none d-md-block d-lg-none">MD</span>
    <span class="badge badge-secondary d-none d-sm-block d-md-none">SM</span>
    <span class="badge badge-secondary d-block d-sm-none">XS</span>
</div>
<!-- /DEBUG -->