Applying Empty Alt Text
By default, a new image does not contain an "alt" (alternate text) attribute when you insert it into a topic or snippet, unless you specifically add alt text in the Insert Image dialog. However, alt attributes on images are required for Section 508 compliance, even if the string is empty or null (alt=""). Also, by adding empty alt attributes to images, you can search the files to find the images without alternate text and then add it as needed.
You can use a global setting in the Options dialog. This automatically adds an empty alt tag to images when you insert them into a topic or snippet (unless you specifically add an alt tag to an image).
In addition to images, this also works for QR codes and equations, since those elements are converted to images in the output.