TYPO3 Core

Yes, it seems really confusing, however, as you pointed out, colPos_list deals with column numbers, whilst remove items deals with entires in the list (and is independent from colPos_list, as it works for every field of every table).

Reordering the entries in tt_content.colPos might lower the confusion, however break existing sites.

So I would say: won't fix, sorry...

well, but then the behaviour is not consistent with older versions of TYPO3, since this IS breaking existing sites.

Just for clarification: if you use this code in TSconfig:

mod.SHARED.colPos_list = 0,2
TCEFORM.tt_content.colPos.removeItems = 1,3

this will have the following effect:

in version 4.4.6 and below: in column view the normal and right columns are displayed and in content elements you can only select normal and right columns in the column select box.
The TCEFORM.tt_content.colPos.removeItems configuration ONLY affects the form

In version 4.5beta4/rc1: in column view only the right column is shown, the normal column does not exist anymore. In content elements you can still select normal and right columns.
The TCEFORM.tt_content.colPos.removeItems configuration ALSO affects the column view.

Ah, okay.. I misunderstood. You didn't write that behavior has changed.

So this has to be investigated..

So if I got you right and from my own experience trying to reproduce this bug:

This one is buggy
TCEFORM.tt_content.colPos.removeItems

while this one is OK
mod.SHARED.colPos_list = 0,2

so we just have to care about colPos.removeItems ?

I guess I nailed down the problem:

It seems as if getColPosListItemsParsed in class.tx_cms_backendlayout.php behaves completely strange and does not what was intended.

Will come up with a patch today.

I think I got it now:
removeItems ALSO affects the column view to make sure the user won't be able to create new content in a column that he is not allowed to use. This is a new behaviour introduced in 4.5, but it won't necessarily break existing stuff, unless the implementation is as buggy as it is i RC1.

BUT: The bug is just about the array key, which does NOT represent the actualy colPos Key used by the item. After fixing that, the keys match each other, so removeItems works as expected.

Attached V2 fixes an additional bug: Pages with backend layout "none" should always show the default columns.

Committed to trunk, rev. 10287. Will be included in 4.5 RC2