your question is asked quite often, so there's a lot of posts here about the subject.
bottom line is slide supports are holdovers from the early days of slideouts, when they were often called tipouts.
back then, slide technology was not great and many had to use supports.
now, the technology is stable and slides don't need them. in fact, manufacturers warn not to use them and if you do, you may void the warranty.
you should have a sticker or warning in your manual stating NOT to use slide supports.
and Zoe the Wonder Dog(R.I.P.)
'07 Roo 23SS pushing an '07 Chevy Avalanche
Equalizer WDH and Prodigy BC