Problem Description

The default behavior of markdown to html is to parse image dimensions despite options.parseImgDimensions being false, i.e. with the default options, the following markdown is valid, and converts to the following html:

![my image](./pic/pic1_50.png =100pxx20px)

![my image2][1]

[1]: ./pic/pic1_50.png =100pxx20px

<p><img src="./pic/pic1_50.png" alt="my image" width="100px" height="20px" /></p>
<p><img src="./pic/pic1_50.png" alt="my image2" width="100px" height="20px" /></p>

The Fix

Fixing this issue requires two things in my opinion:

1. In order to not break existing usage, the default should be changed to true both in code and in the documentation.
2. When the option is false image dimensions should be rejected

Desired behavior with parseImgDimensions set to false

The above markdown should be rejected as valid image markdown and converted to the following html:

<p>![my image](./pic/pic1_50.png =100pxx20px)</p>
<p>![my image2][1]</p>
<p>[1]: ./pic/pic1_50.png =100pxx20px</p>