Just remove the md5 function call:

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<img src="/avatar/' . trim($node->nodeValue) . '.png" alt="" />
%

thnx dude! and then the code for the default icon part.. :P

haha learning these things is hard. I almost got it right, but i missed the 'trim' part.

I think it would be easier to make it so that if username.jpg doesnt exist, there would be no avatar printed at all. But as u can see, im having a hard time putting these things into a form of code.

if(file_exist).......

The thing with the md5 is, that i have no clue what it is and how to convert usernames into md5 :) But huge thanks for the code!

Hey im starting to learn something. Im trying to change the code to make it display a default avatar in case username.png doesnt exist. If such a .png doesnt exist, how do you point to a default .png -file to appear? im pretty comfortable with html but this is waaaay more complicated :P

Then you could alter the code above to:

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/* Put this in theme.php, inside the `theme_custom` function. */

	foreach ($template->query('.nnf_reply-author, #nnf_post-author') as $node) {
		// The file we want, md5 of the user name and the PNG extension:
		$filename = md5(trim($node->nodeValue)) . '.png';
		// The avatar directory on the server, I am assuming in the forum root:
		$avatardir = FORUM_ROOT . DIRECTORY_SEPARATOR . 'avatar' . DIRECTORY_SEPARATOR;
		// Test if the file exists in the directory:
		if (!file_exists ($avatardir . $filename)) {
			$filename = 'default.png';
		}
		// Write the HTML for the avatar:
		$value = '<img src="/avatar/' . $filename . '" alt="" /> '
		       . $node->nodeValue;
		$node->nodeValue = '';
		$frag = $node->ownerDocument->createDocumentFragment();
		if (!@$frag->appendXML($value) || !@$node->appendChild($frag)) {
			throw new Exception("Invalid HTML");
		}
	}
%

I didn't change much except the layout of the code. As with previous version, it still checks for the avatar of the user, but now falls back to the default one. The default avatar is named `default.png`, and should be in the avatar directory.

I got this working, but for the basic understanding of the code structure, ill need to start studying hard.

Thank you guys so much!

Hi @Martijn

I already add this code to my theme.php but my forum still cannot embed youtube video.
Anything I need to alter / add ?

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/* Put this in theme.php, inside the `theme_custom` function. */

	foreach ($template->query('.nnf_reply-author, #nnf_post-author') as $node) {
		// The file we want, md5 of the user name and the PNG extension:
		$filename = md5(trim($node->nodeValue)) . '.png';
		// The avatar directory on the server, I am assuming in the forum root:
		$avatardir = FORUM_ROOT . DIRECTORY_SEPARATOR . 'avatar' . DIRECTORY_SEPARATOR;
		// Test if the file exists in the directory:
		if (file_exists ($avatardir . $filename)) {
			$value = '<img src="/avatar/' . $filename . '" alt="" /> '
			       . $node->nodeValue;
			$node->nodeValue = '';
			$frag = $node->ownerDocument->createDocumentFragment();
			if (!@$frag->appendXML($value) || !@$node->appendChild($frag)) {
				throw new Exception("Invalid HTML");
			}
		}
	}
%