hallo,

we have some strange performance behaviour in IE here. I use VS13 and IE11 on Windows 8.1.

we use the ig.loader with many grid features. 

opening the webpage with recent FF or Chrome renders the grid in less than 2 seconds. opening it with IE stucks and takes forever. 

See the screenshots of my gui profiling in IE, always the last iggrid.ui.feature.js file (after changing features, another last-file is affected) has a fast exclusive execution time, but the inclusive time takes forever (100% cpu, IE hangs) . 

http://1drv.ms/1nTMg1P  - infragistics.ui.grid.summaries.js hangs

http://1drv.ms/1nTMAO5  - same grid but summaries feature deactivated. now infragistics.ui.rowselectors.js hangs

http://1drv.ms/1nTMTZo   - same grid, changed features. now infragistics.ui.sorting.js hangs

any idea what's happening? I reseted my Internet Explorer to default settings, rebooted and opened the webpage on an IIS webserver and everything was fine. starting visual studio and debugging with IISExpress in IE,  it hangs again. that's not only on my PC, all developers here experience this issue. after debugging once with visual studio, it does not only hang during debugging session, it also hangs at opening the page from IIS webserver.

I deleted webessentials extension of VS, I deactivated break and continue, deleted the solutions .suo files,  we have no idea what's happening.

edit: if I change the document mode in IE debug tools (F12) to IE10, it hangs too. but if I change it to documentmode IE9, it doesn't.

edit: by the way: we include the ig.loader.js file once in our pages, but $.ig.loader(....) is called for every grid on that page (up to 8 grids [we know that many grids on one page can issue performance problems, but it's very fast in FF, Chrome and IEs on "non-developer" PCs] ;) )