This page has a green "completed" flag... but I don't see any mention that this is indeed done.

Using the latest version of Telerik (as of 12/26/2018) and this still doesn't work.

This behaviour really needs by default.

This shouldn't be set to complete.  You are asking EVERY application developer to add this to EVERY application they write that needs a numeric textbox.  Why is it the default for nearly all other controls?  At least be consistent.
You force many Mb of files on us with the default Telerik ASP.NET Core application, it wouldn't be much to ask to add a few more bytes.
Remember it takes time for developers to find the behaviour, possibly even in QA, then find this answer, apply it, rebuild, and retest.

I just want to voice my agreement that the solution provided is not adequate and developers should not be expected to implement hacks to provide expected default behavior.

The link posted as a solution isn't very applicable when you're in an AngularJS app, especially when you've created several numeric textboxes in a table created with an ng-repeat

This should be the default behaviour, as expected after using other input controls. With a hacky java based 'fix' I think this really lets the toolset down.

I'm using MVC Grid InCell edit mode. This doesn't work for us. Please advise.

The provided solution doesn't work for me in an angular application  :(

For me the given solution is only a (annoying) workaround for me.
Selecting text on focus should be the default out of the box, because that is the behavior that a user expected.

Are you kidding Kenshin? 
This is browser default behavior for inputs and you're saying we have to hack it in ourselves? 
That's not a solution mate, that's a bug.

I would like to see this in next release...

Yes, I agree, It's very annoying not to have have it when you're navigating with tab key

My clients just complained to me about this. My afternoon.... finding work arounds.

Yes, I agree too

I do agree that this should be the default behaviour. My customer require that all text is selected when tabbing becasue a lot of data need to be modified in a rapid and smooth consistent way, and minimize humen to enter uncorrectly values. The user case is application for controlling electrical devices in heavy oil pipe industry with a lot of numeric settngs.

I agree this should be a default.  

I agree that this should be a default

nuts that this isn't the default

this is how an in put box works and this is how the numerictextbox should work as well.

Also, if you modify the source you'll need to add that.element[0].select(); at the end of the _focusin method a little below the _click method.

I definitely agree with this.  I would also say that focus should happen after the Kendo events or there should be some kind of focus event we could bind to on the NumericTextBox control to run code after the kendo code.  The problem child is the setting of the caret position in the _click function which seems to be happening after all the focus code.  If you have the source you can search for caret(that.element[0], caretPosition); and comment it if you'd like.

If you add select all to the numeric text box the same thing should be added to all controls.  I think this would be good to add as a configuration option.