Resize slow on Firefox

[expertmo]

H everybody,
I have an application with a very complex and 'hard' layout: it's a tab panel, with 10 tabs inside.
Each tab it's a border layout (with fittoparent plungin) with a north region very simple with some form field, but with a center region that contains 5 grids organized in a column layout (each column has a fit layout type in order to size correctly on the column).
Everything is mainly organized in a vieport.
I have the following problem: when i resize my browser window, everything is very fast under IE (version 8), but on firefox is tremendous slow, also with firebug closed.
I've already tried to reduce the number of rows on my grids with a paging toolbar, and I removed every not need nested panel or layout level.

Is that a common problem? There's really a tremendous difference between the two browsers, on Firefox is almost unsable.

Any suggestion will be appreciated.

Thanks
AD

[Animal]

(with fittoparent plungin)

Not necessary.

Layouts perform sizing.

It's what they are for

[Animal]

(each column has a fit layout type in order to size correctly on the column)

BZZZZT! Why would you WRAP a grid in a fit layout Panel?

Want 5 grids side by side? (And I can't imagine why you would) then use a Container configured

{
    xtype: 'container',
    region: 'center',
    layout: {
       type: 'hbox',
        align: 'stretch'
    },
    items: [grid1, grid2, grid3, grid4, grid5]
}

(Where grids are configured with flex)

[expertmo]

Thanks Animal! The hbox is my solution!
I need the 5 grids because I need to make a sort of immediate comparison between 5 differents search results.
On the fittoparent, I use it because I don't want to give a fix height for my components and in order to avoid scrolls. Using fittoparent plugin I have the border region always with the right dimension.
I'm sorry I did not think about HBOX layout, I modified my code with your direction and now the resize time is really better.

Thanks again!
AD

[Animal]

Nope.

You do NOT need FitToParent