It seems you have pasted this code in a wrong place... most possibly before <?php tag...
You must be experienced enough to edit files that way.

Sorry I forgot put the code between <?php and ?>

/* Preview addon */
if(isset($_POST['prevForm']
) and $_POST['prevForm']==1) include($pathToFiles.'addon_preview2.php');
/* --Preview addon */

in bb_plugins.php .Now is working fine

Thanks Paul

When i have set one or more linebreak <br /> in an languagevariable, eg $anti_guest_rule1, then it works fine in the output from main_posthold, but not in preview-window. There i see the warningtext and the tags <br />. My mistake?

You are just the first person in the world trying to put straight HTML in the language variable.
Nowhere it's written that you will achieve the desired effect with it ;)
To let the preview working fine with <br /> tags, you should remove or replace them to newlines in advance, before the text is being output in preview's add-on.
You may modify addon_preview.php and add the following code:

Are you sure? Have a look at the language-file eng.php in the lines 68, 269, 417 an 418 :)

And in my preview
Because of spamming issues:

You are not allowed to post outgoing links, URLs or email addresses.

looks better than
Because of spamming issues, you are not allowed to post outgoing links, URLs or email addresses.

But is it a matter of taste, .. said the monkey and bit in the soap =8). And thanks for the code, works fine!

I was meaning the language for anti-guest add-on.
It's good if it works :)

When i post as reg user and previw the post, i see there my username in the top. A Guest but also has a name, language-file default setting under $l_anonymous, or a freely chosen name .. but which can not be displayed? Would it look nice, or? But not now, I would absolutely have to be, I just noticed.

In default version, the username should not be displayed at all.
So I am a bit confused as I don't understand what you are about?..

It's Done. It was about the display of the user name in the Preview window. I have the template adapted and applied in bb_plugings a separate variable.

When a guest opens the preview window then there is the name Guest on the top, otherwise, the name of the registered users. Sorry Paul, if I can express myself in English mostly wrong.

Ok. It's up to you how you moderate your custom implementations :)
I can't have an idea what's done on your end.

Hello,

I don't know why, but I just can't make the preview button work.
Used compiler version without touching anything else, installed manually, inspected the files many times, tried other browsers... Still, when I click on it, nothing happens. Inspecting the page with my browser tells me : Uncaught ReferenceError: previewMessage is not defined
I have no idea what to do next, I could use some help ! :)

By the way, the colorpicker isn't working on the main page, it's only working inside a topic.

Stan
I've tested how the Preview add-on works, if embedded using the Compiler, and it's definitely all OK. But I've tested only this add-on and nothing else. Do you have other add-ons installed, and if so, which ones?

From seeing your report, I could conclude, that you may have some external JavaScript code, for example, in the header file or anywhere else, and which could be about your code - and that code could be wrong. If there's something wrong in your own code, then all other valid codes will also not execute, and the browser could throw errors like the one you described. So just check carefully all your JavaScript codes; at least, you may try the clean miniBB install without any add-ons, and then add the add-ons which doesn't work on your end, manually one by one.

Hi Paul,

The other add-ons I used are :

Anti-Guest
Unread Messages Indicator using Cookies
Direct Emailing
All forum moderation extensions
Profiles Checker
Standalone New Topic Form
and every Extra Buttons / BB-codes

I used the Compiler. Everything else was left entirely untouched. No code added, nothing modified. Just a clean install.
I don't know if this can be revelant, but the server I installed minibb to already hosts a Wordpress site, and is using php7.

I will try again later with only the preview addon.

You know my email. Send me the Compiled package you've got, I will try it on my end.