Buttons CSS problem (on existing site installation)
I've installed the Mentor theme on an existing Drupal site and it seems to be a problem with the buttons: the only button that have css applied is the Save buton, all the rest of the buttons have no css applied, even the default css it's not applied. For example, the preview and delete buttons don't have css; all the buttons from views displays don't have css applied; etc.
However, if I create a new button, it's applying the css that I select.
All the instructions are followed, all the cache is cleard. I've checked with the inspector, the classes do not appear (check the attachment -> an example with the save button which is ok and the preview button which don't have the btn css applied).
Also I've seen other small css problems with radio lists (label is shown under radio check), table-stripped not applied, or the Inline Entity Form is having by default the row weights activated and you can't disable them.
PS: The new installation is working perfectly.