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Description

What?

Wikipedia currently uses two colours for links, namely blue for existent articles and red for nonexistent articles. This proposal suggests using orange for stubs. The goal is to engage readers in article contribution, specifically stub expansion.

Why?

Micro-opportunities for user participation already exist, such as red links, but Wikipedia needs more. Red links serve for article creation, but are nowadays rare. In effect, the focus is now on expansion and improvement, rather than creation. With most links blue, the reader is given the impression that work is no longer needed. Orange links are an attempt to address this illusion, and create new engaging micro-opportunities. What is more, readers will be lead to these stubs from their current read, making the links potentially relevant.
Specifics

How?

Using scripts similar to this one and this one.

For who?

For all readers by default.

Why orange?

Because similar to red, underlying the similarity between stubs and nonexistent articles.
Potential problems

Stub articles are not necessarily articles that people want to edit.

Yes, but orange links, like red links, are merely suggestions.

This proposal assumes that stubs are Wikipedia's worst articles.

No assumption of quality is given, orange links point to a subset of articles that need most expansion.

This adds complexity to the linking system, will cause confusion, and eople will not understand orange links even after clicking one.

Testing only will determine if the added complexity is a real problem.
Other issues

Some undeveloped articles have no rating.

Links to these articles we be blue until appropriate rating is done.

There are potential performance problems.

No programmer has expressed his concern as of yet.

Colourblind cannot distinguish orange/red or orange/blue.