Chrome extension for testing WCAG 1.4.12.a Text Spacing — and it seems to work with iFrames! https://chrome.google.com/webstore/detail/text-spacing-editor/amnelgbfbdlfjeaobejkfmjjnmeddaoj/ #a11y #tools
Text Spacing Editor

A tool for editing text spacing properties on web pages. WCAG conformance information included.

@WebAxe Since I avoid adding extensions from unknown sources, other than the ability to change values in a UI how is it different from Steve’s bookmarklet (https://codepen.io/stevef/pen/YLMqbo)? As in, I am assuming you are using it and have some insights.
text spacing bookmarklet

...

@aardrian I have used it. There was a Slack thread from the author. You can reset without reloading page. Also has slider controls for the 4 typography settings.
@WebAxe @aardrian obligatory rant about how the "at least" in the wording for that SC is actually rubbish/misleading ... you'd only ever test at those exact values specified (as opposed to other uses of "at least" in WCAG where it sets a threshold value)