header array empty in theme.inc TypeError: strlen(): Argument must be of type string, array given in Unicode.php

Are you able to reproduce this with vanilla Drupal core?

Can you please provide steps to reproduce starting f from install Drupal?

Thanks

The extra [] was added in 📌 Allow for deletion of a single value of a multiple value field Fixed but not sure how to reproduce the issue.

I am having the same problem, I don't know why because a vanilla Drupal install didn't get that error, but adding an override of that function and making [] to ' ' fixed it.

Are you using Bootsrap theme? May be a duplicate of 🐛 PHP error when form has entity reference in Drupal 10.2.0 RTBC .

Yes, Patch Issues-3409370-PHP-error-when-form-has-entity-reference.patch
solve the problem but for me is a core problem not bootstrap theme problem :
function template_preprocess_field_multiple_value_form add a empty array, why ?

@larowlan - steps to reproduce using Bootstrap theme are described in 🐛 PHP error when form has entity reference in Drupal 10.2.0 RTBC , reproduced here:

1. Drupal 10.2.0 standard install profile with bootstrap 3.29.
2. Ensure bootstrap theme active for creating content - either login as a non-admin user or disable Use the administration theme when editing or creating content at /admin/appearance.
3. Edit the article structure to add a new field:
1. Label = Users
2. Field type = Reference
3. Reference type = User
4. Rest as default
4. Add article content (/node/add/article) - page loads OK.
5. Go back to the Users field settings and set the Allowed number of values to a value > 1 or Unlimited.
6. Add article content (/node/add/article) - page fails to load and PHP error is observed in log.

To @aduthois' point - is this considered a core issue or should the fix be in Bootstrap?

I suppose if drupal core has a good reason to add an empty array, boostrap should adapt to the case. So ok for this patch

I am having this problem.

The documentation for template_preprocess_table() says that the array values in the #header property need to be either a string or an array with certain keys. An empty array is not consistent with the documentation. Correcting it makes sense for this reason. The attached patch does this and fixes the issue for me.

There is an underlying issue here as well: As it is, there is an empty th element created. That shouldn't be. One option would be to give the column a title, perhaps "Actions". Another would be to remove the cell and increase the colspan of the previous one; see this patch for implementation.

Recommend using an MR, as DrupalCI is less supported and may not be as accurate in my opinion.

But currently the patch is showing failures.

Also will need test coverage

Issue summary should be updated with standard template. Added the template but will have to be updated.

I have created a merge request with the patches.

Hi! Comment #10: drupal-header_array_empty-3409752-10.patch works for me. Thanks!

Hello,

I have the same issue but for D9.5.11 :
The patches are non applicables. Do you have an idea to solve that issue ?

TypeError: strlen(): Argument #1 ($string) must be of type string, array given in strlen() (line 477 of core/lib/Drupal/Component/Utility/Unicode.php).
strlen(Array) (Line: 477)
Drupal\Component\Utility\Unicode::validateUtf8(Array) (Line: 65)
Drupal\Component\Utility\Xss::filter(Array, Array) (Line: 753)
Drupal\Core\Render\Renderer->ensureMarkupIsSafe(Array) (Line: 380)
Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 204)
Drupal\Core\Render\Renderer->render(Array) (Line: 479)
Drupal\Core\Template\TwigExtension->escapeFilter(Object, Array, 'html', NULL, 1) (Line: 50)
__TwigTemplate_2521555a241b9ba0b3f8cdba9a2b0ebc->doDisplay(Array, Array) (Line: 405)
Twig\Template->displayWithErrorHandling(Array, Array) (Line: 378)
Twig\Template->display(Array) (Line: 390)
Twig\Template->render(Array) (Line: 55)
twig_render_template('core/themes/claro/templates/form-element-label.html.twig', Array) (Line: 384)
Drupal\Core\Theme\ThemeManager->render('form_element_label', Array) (Line: 433)
Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 204)
Drupal\Core\Render\Renderer->render(Array) (Line: 479)
Drupal\Core\Template\TwigExtension->escapeFilter(Object, Array, 'html', NULL, 1) (Line: 60)
__TwigTemplate_661ab2f707079e55824bbaecf556a958->doDisplay(Array, Array) (Line: 405)
Twig\Template->displayWithErrorHandling(Array, Array) (Line: 378)
Twig\Template->display(Array) (Line: 390)
Twig\Template->render(Array) (Line: 55)
twig_render_template('core/themes/claro/templates/form-element.html.twig', Array) (Line: 384)
Drupal\Core\Theme\ThemeManager->render('form_element', Array) (Line: 489)
Drupal\Core\Render\Renderer->doRender(Array) (Line: 446)
Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 204)
Drupal\Core\Render\Renderer->render(Array) (Line: 479)
Drupal\Core\Template\TwigExtension->escapeFilter(Object, Array, 'html', NULL, 1) (Line: 89)
__TwigTemplate_683f4aab1c1850ba7b0b2ff00cc5518b->doDisplay(Array, Array) (Line: 405)
Twig\Template->displayWithErrorHandling(Array, Array) (Line: 378)
Twig\Template->display(Array) (Line: 390)
Twig\Template->render(Array) (Line: 55)
twig_render_template('core/themes/claro/templates/form/field-multiple-value-form.html.twig', Array) (Line: 384)
Drupal\Core\Theme\ThemeManager->render('field_multiple_value_form', Array) (Line: 433)
Drupal\Core\Render\Renderer->doRender(Array) (Line: 446)
Drupal\Core\Render\Renderer->doRender(Array) (Line: 446)
Drupal\Core\Render\Renderer->doRender(Array) (Line: 446)
Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 204)
Drupal\Core\Render\Renderer->render(Array) (Line: 479)
Drupal\Core\Template\TwigExtension->escapeFilter(Object, Array, 'html', NULL, 1) (Line: 179)
__TwigTemplate_5bcd06882cab0ed5e3210b27209930bc->doDisplay(Array, Array) (Line: 405)
Twig\Template->displayWithErrorHandling(Array, Array) (Line: 378)
Twig\Template->display(Array) (Line: 390)
Twig\Template->render(Array) (Line: 55)
twig_render_template('core/themes/claro/templates/classy/dataset/table.html.twig', Array) (Line: 384)
Drupal\Core\Theme\ThemeManager->render('table', Array) (Line: 433)
Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 204)
Drupal\Core\Render\Renderer->render(Array) (Line: 479)
Drupal\Core\Template\TwigExtension->escapeFilter(Object, Array, 'html', NULL, 1) (Line: 56)
__TwigTemplate_683f4aab1c1850ba7b0b2ff00cc5518b->doDisplay(Array, Array) (Line: 405)
Twig\Template->displayWithErrorHandling(Array, Array) (Line: 378)
Twig\Template->display(Array) (Line: 390)
Twig\Template->render(Array) (Line: 55)
twig_render_template('core/themes/claro/templates/form/field-multiple-value-form.html.twig', Array) (Line: 384)
Drupal\Core\Theme\ThemeManager->render('field_multiple_value_form', Array) (Line: 433)
Drupal\Core\Render\Renderer->doRender(Array) (Line: 446)
Drupal\Core\Render\Renderer->doRender(Array) (Line: 446)
Drupal\Core\Render\Renderer->doRender(Array) (Line: 446)
Drupal\Core\Render\Renderer->doRender(Array) (Line: 446)
Drupal\Core\Render\Renderer->doRender(Array) (Line: 446)
Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 204)
Drupal\Core\Render\Renderer->render(Array) (Line: 479)
Drupal\Core\Template\TwigExtension->escapeFilter(Object, Array, 'html', NULL, 1) (Line: 44)
__TwigTemplate_a452e371f89bc4dde9344d99b72c7065->doDisplay(Array, Array) (Line: 405)
Twig\Template->displayWithErrorHandling(Array, Array) (Line: 378)
Twig\Template->display(Array) (Line: 390)
Twig\Template->render(Array) (Line: 55)
twig_render_template('core/themes/claro/templates/node-edit-form.html.twig', Array) (Line: 384)
Drupal\Core\Theme\ThemeManager->render('node_edit_form', Array) (Line: 433)
Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 204)
Drupal\Core\Render\Renderer->render(Array, ) (Line: 242)
Drupal\Core\Render\MainContent\HtmlRenderer->Drupal\Core\Render\MainContent\{closure}() (Line: 580)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 243)
Drupal\Core\Render\MainContent\HtmlRenderer->prepare(Array, Object, Object) (Line: 132)
Drupal\Core\Render\MainContent\HtmlRenderer->renderResponse(Array, Object, Object) (Line: 90)
Drupal\Core\EventSubscriber\MainContentViewSubscriber->onViewRenderArray(Object, 'kernel.view', Object)
call_user_func(Array, Object, 'kernel.view', Object) (Line: 142)
Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch(Object, 'kernel.view') (Line: 174)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 81)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 58)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 130)
Drupal\cdn\StackMiddleware\DuplicateContentPreventionMiddleware->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 23)
Stack\StackedHttpKernel->handle(Object, 1, 1) (Line: 718)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)

@hdnag your issue must be caused by something else. This issue is about a bug introduced in Drupal 10.2. Drupal 9 in no longer supported.

@Liam Morland, thanks #10 in my case resolves the bug.
@smustgrave, is there anything else (test coverage?) that is needed to get this issue across the line?
Many thanks.

It should have a test.