What is "Render in classic mode" doing?

[Qlxr]

when i check this feature, my scroll bar just gone? 

any one know what is this feature really doing?

[AKotb]

we have made a recent rewrite of some of of the core components and we wanted to have a way to go back to the old infrastructure in case there is a problem in the new one.

if your app is working fine when this is turned off, then that is awesome :), if you found a problem that recently that gets solved by turning on the classic mode then lets us know and we will investigate it.

Thanks

[wyotim]

@AKotbI had to turn this feature on for a couple of our apps as unhiding items (buttons, galleries, shapes) would have vertical stripes missing. Also, it was rendering some pages quite slowly. Granted, these pages are pretty graphically heavy, but turning on the classic mode fixed everything.

[AKotb]

can you explain more what "unhiding items (buttons, galleries, shapes) would have vertical stripes missing." means ?

is it scrollbars ?

[wyotim]

No. I have hidden items, such as a form to edit information, that becomes visible when the user presses a button. Without the classic mode active, there will be vertical stripes of that form that are transparent. Sort of like if someone erased a vertical section of the form. No scroll bars involved.

Vertical stripes missingClassic render mode

[AKotb]

This happens in the published app not the studio right ?

also do you use the desktop player or the web player ?

does it work correctly if you run it in the web player ?

[Qlxr]

just test it again,

with it turns on , 

1. in IE , the Gallery with Flexiable height, has Scroll bar, but not content. 
2. in Chrome, the Gallery with Flexiable height,  has no Scroll bar, everthing else is ok. 

generally, i feel now the APP is really slow, if turns it on ,it is faster, much more. 

not in studio mode , web mode. 

[wyotim]

@AKotbIt is in the desktop player. My users don't (and won't) use the web player so I don't test it there. Most of our apps require offline capabilities, so the web player doesn't do us much good. (Of course, the desktop player doesn't do us much good in that regard either but that is another topic.)

[pulsebeat]

Per your message to "let us know" if something gets solved by turning on classic mode, please see this posting....

https://powerusers.microsoft.com/jgvjg48436/board/message?board.id=PowerAppsForum1&message.id=45106#...

[Qlxr]

The Problem still, 

to turn on Classic mode, you will lose your scroll bar in "Chrome" . 

to turn off Classic mode, the app will perform very slow !!!