A technical question.

[cluseb]

How do I post a non left Click Expandable Attachment ?
link to example the second and third attachments
http://ralphus.net/thegimpforum/viewtopic.php?f=3&t=35

[BobDarkroom]

How do I post a non left Click Expandable Attachment ?
link to example the second and third attachments
http://ralphus.net/thegimpforum/viewtopic.php?f=3&t=35

Not sure I understand your question.
A link is left clickable by definition otherwise it wouldn't be a link.

[letvor]

Same here.
Maybe if you provide a detailed (step by step) description of what you have in mind when you say: "non left Click Expandable Attachment" someone will be able to help you.

[cluseb]

Same here.
Maybe if you provide a detailed (step by step) description of what you have in mind when you say: "non left Click Expandable Attachment" someone will be able to help you.

link to example the second and third attachments
http://ralphus.net/thegimpforum/viewtopic.php?f=3&t=35

[BobDarkroom]

Same here.
Maybe if you provide a detailed (step by step) description of what you have in mind when you say: "non left Click Expandable Attachment" someone will be able to help you.

link to example the second and third attachments
http://ralphus.net/thegimpforum/viewtopic.php?f=3&t=35

That's not the answer I was expecting. Your question wasn't very clear and I expected a bit more information about what you were looking for as pointed out by letvor as well. Anyway, I think I understood your question after looking at the example page.
The first image will expand when left clicked, the 2nd and 3rd are not left clickable and you want to know how you can achieve that with your attachments, right?
Well, as far as know, you can't with inline attachments that you add to this site yourself.
The 2nd and 3rd images on the example page are not in line attachments but links to images on another site. If left clicking images is disabled on that site, you won't be able to expand them with a left click on this site either.
However, what's the point? You can still expand them by right clicking on the image and selecting "Open in a new tab".
There's even an advantage when doing it that way : as it opens a new tap, the expanded image will not replace the page you were on as it happens with left clicking. You can simply close the new tab and you'll still be on the forum page.
Btw, this works with in line inserted images as well.