Presently in Spreadsheet tooltip is not working for filter applied range 
so tooltip should display for each cell in which the range of filter is applied

I know that Kendo Spreadsheet works like most popular Spreadsheets (Excel and Google Spreadsheet) where, if you copy or drag and paste values from cells, you will copy also the styles, validations, etc from that cell to the new one (unless you select "paste values only" in a context menu or ctrl + shift + v). 

It would be awesome if we can set how this works by configuring a property in the Spreadsheet configuration, something like pasteValuesOnly: false/true or even more complex with an object where you can choose if paste values, validations, formulas, styles or whatever. Also you could attach this functionalities to a context menu (as Google Spreadsheet does) and be able to paste everything, values only, format only, formulas or data validation.

Can the Spreadsheet widget be updated to initialize a sheet that is bound to a datasource when the datasource is an empty object?  

Generally, when a sheet is bound to a datasource, it is for the purpose of editing data, creating new rows and updating/deleting existing rows.  If a datasource comes back empty, the sheet isn't initialized.  So there are no column headers, which can be confusing to users when they don't know what data to enter in which columns.  The other thing is that the sheet itself is not fully initialize so that even if we assign column headers programmatically, when users start entering data, the UI becomes unresponsive and generates a javascript error: Uncaught TypeError: Cannot read property 'indexOf' of undefined
    at r.set (kendo.all.js:4586)
    at r.set (kendo.all.js:4760)
    at kendo.all.js:127702

Set an indicator same way that grid already does but now in sheet cells when a record is 'dirty'.

DefaultCellStyle property in spreadsheet has a field “Wrap”, but doesn’t have a field “Format”. For example, if I need to process all cells as text, I must set the field “Format” on a client side:
sheet.range("A1:AX200").wrap(true).format("@");
It works.
But the initialization of the range ("A1:AX200") takes time… It is not very fast…
It would be better to have the field “Format” in the DefaultCellStyle property in spreadsheet…

I need the way to get a user the opportunity to set the columns headers. Moreover, the columns headers should be saved separately from the main spreadsheet data.

Of course, the possible variant is to have two spreadsheets: the one – for the data, the second (with one row) – for the headers.

But the better way is to get a user the opportunity to set the spreadsheet columns headers.
It would be ideally if a user could change “A”, “B”, “C” for “ID”, “Product”, “Quantity” …
Not to have a first row for headers, but change the spreadsheet columns headers!
Moreover, we have the context menu on the columns headers and it is possible to add one more item “Edit” in it.

I am working on a project where i am using KendoUI components. I have to show a financial sheet. All formulas are working fine like SUM,INDIRECT etc. but IRR not working as expected.

Tested IRR formula outside my project and the same happened.

Additional functionality for:
-- Conditional Formatting -- coloring of cells, for example based upon a value and then be able to import from excel, and export back out.
-- Data Validation (dropdowns).  Also be able to import and export back out.

It would be useful if copy and paste the data have the option of fill the series or copy the value for the date format. 
Furthermore, copy from multiple column value and allow to paste multiple copied value from the spreadsheet will be added advantage. 

Thanks. 

For KendoUI Spreadsheet, it should have the ability to add images or logo into the spreadsheet. This feature is already available in Handsontable component.

We are using the Kendo UI spreadsheet in a real-world website. We have a design team who are providing a visual design which fits in with our company's corporate standards.

HTML5 aims at separating styling from the layout design, which enables different teams to build the syle, with very little development experience, but more artistic experience.

For some reason, the Spreadsheet control can only be styled via the API (javascript code)! This means our design team needs to write their style in javascript, which is completely unrealistic.

It should be a fairly simple change to allow a range object to have a CSS class associated, and let HTML work like it should.

In the scpreadsheet you can use controls like  dropdowns & datepicker , but should be helpful if user could to customize the design and behavior. 

For example, the dropdown and any other control needs be opened since an icon at right that is displayed over the next column, As user i would like to choose how i want to be displayed the control: Open clicking on it, set expand direction, styles, etc.

Support scenarios where users can use the spreadsheet component to design templates with disabled cells.

I appreciate that this can be customized (as almost anything) but note this is the only cell property that is not configurable via the toolbar.

Add menu item that allows end users to style background and text color based on rules (if cell value > 0 then green)

can add float object container ? eg:charts

Need a default cell format, in addition to rowHeight and columnWidth including:
- font size,
- font-family,
- font weight
- (see other toolbar options)

Default cell format would set the default values for all cells and toolbar options.

Enable Cut/Copy cell values and can Paste it in mutiple selected values

On excel, you can filter merged rows. On the kendo spreadsheet widget, filtering on merged rows is not possible. It would be a very useful feature for us. 

Also worth noting is that if you convert an excel file to JSON using Telerik RadSpreadProcessing, and load the kendo widget with the JSON, the widget displays a filter icon but clicking it loads a non-functioning filter. Wouldn't it make more sense to load with a message along the lines of 'You loaded a spreadsheet with filters applied to merged rows, which is not supported in this widget'. Otherwise it's quite confusing to our users.

E.g. italian culture uses ";" as parameter separator in formulae.
Our client will adopt spreadsheet component on a global basis and users need to be able to e.g. copy/paste from excel to spreadsheet component using their culture