[5.x] Page children as value for field conditions

[heidkaemper]

This PR relates to #11080

Sometimes it would be helpful to conditionally render a field when the page is part of a structure and has / has not children.

if:
children: 'not empty'

Or even something like this:

if:
children: 'contains c534de98-24c8-479b-b1a0-0e8945b76020'

By the way, this PR started with the need for a has-children field condition. But I switched to children because I think it's a bit more flexible.

[heidkaemper]

This PR relates to #11080

Sometimes it would be helpful to conditionally render a field when the page is part of a structure and has / has not children.

if:
children: 'not empty'

Or even something like this:

if:
children: 'contains c534de98-24c8-479b-b1a0-0e8945b76020'

By the way, this PR started with the need for a has-children field condition. But I switched to children because I think it's a bit more flexible.

[heidkaemper]

This PR relates to #11080

Sometimes it would be helpful to conditionally render a field when the page is part of a structure and has / has not children.

if:
children: 'not empty'

Or even something like this:

if:
children: 'contains c534de98-24c8-479b-b1a0-0e8945b76020'

By the way, this PR started with the need for a has-children field condition. But I switched to children because I think it's a bit more flexible.

[heidkaemper]

This PR relates to #11080

Sometimes it would be helpful to conditionally render a field when the page is part of a structure and has / has not children.

if:
children: 'not empty'

Or even something like this:

if:
children: 'contains c534de98-24c8-479b-b1a0-0e8945b76020'

By the way, this PR started with the need for a has-children field condition. But I switched to children because I think it's a bit more flexible.

[heidkaemper]

This PR relates to #11080

Sometimes it would be helpful to conditionally render a field when the page is part of a structure and has / has not children.

if:
children: 'not empty'

Or even something like this:

if:
children: 'contains c534de98-24c8-479b-b1a0-0e8945b76020'

By the way, this PR started with the need for a has-children field condition. But I switched to children because I think it's a bit more flexible.

[heidkaemper]

This PR relates to #11080

Sometimes it would be helpful to conditionally render a field when the page is part of a structure and has / has not children.

if:
children: 'not empty'

Or even something like this:

if:
children: 'contains c534de98-24c8-479b-b1a0-0e8945b76020'

By the way, this PR started with the need for a has-children field condition. But I switched to children because I think it's a bit more flexible.

[heidkaemper]

This PR relates to #11080

Sometimes it would be helpful to conditionally render a field when the page is part of a structure and has / has not children.

if:
children: 'not empty'

Or even something like this:

if:
children: 'contains c534de98-24c8-479b-b1a0-0e8945b76020'

By the way, this PR started with the need for a has-children field condition. But I switched to children because I think it's a bit more flexible.

[heidkaemper]

This PR relates to #11080

Sometimes it would be helpful to conditionally render a field when the page is part of a structure and has / has not children.

if:
children: 'not empty'

Or even something like this:

if:
children: 'contains c534de98-24c8-479b-b1a0-0e8945b76020'

By the way, this PR started with the need for a has-children field condition. But I switched to children because I think it's a bit more flexible.