Anyone can submit improvements to the TiddlyWiki documentation that appears on https://tiddlywiki.com. (For improvements to the core code a more complicated process must be used because of the need to test the changes both in the browser and under Node.js before submission).
You should see a pink banner with the text: Can you help us improve this documentation? Find out how to edit this tiddler on GitHub
Click on the external link ...this tiddler on GitHub
You will be prompted that "you need to fork this repository to propose changes". A "fork" is your own copy of the repository that incorporates the changes you are proposing
A new browser tab should open ready to edit the tiddler on github.com
Below the edit box for the tiddler text you should see a box labelled Propose file change
Enter a brief title to explain the change (eg, "Clarify attribute syntax instability")
If necessary, enter a longer description too
Click the green button labelled Propose file change
On the following screen, click the green button labelled Create pull request
Jermolene or one of the other core developers will then have the opportunity to merge your pull request so that it is incorporated into the next build of https://tiddlywiki.com.
Mario Pietsch has created these short video tutorials: