Automatically apply custom alt & title attributes for embedded with BB-code images and attachments (or for attachment list items) instead of file name.
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Maybe the add-on from Nulumia doesn't do that.
Can you send this addon to me in PM? (with the permission of the author)
Or compare the files yourself - Nulumia\SeoTools\XF\BbCode\Renderer\Html::getRenderedAttachment should be completely identical to the fragment above