Whenever the following characters appear in an URL in a link of the form `[foo][1] … [1]: http://...`, the server won't parse it as URL:

* `^`, `{`, `}`, `\`  

and the following won't work in preview:

* `$`, `^`, `*`, `[`, `]`, `{`, `}`, `\`, `'`, `"`

This causes great trouble when copying links from the URL bar. Browsers seldom escape every character, e.g. in Firefox `~!^*_-{}|[]\.` in a query string will not be escaped, while in Chrome ``~!$^*()_-{}|[]\:;',./` won't be escaped. For example, [all 3 Wolfram Alpha links by this user](http://math.stackexchange.com/posts/1911/revisions) fails to appear because of `^`, `{` and `}`. Fixing these links are annoying.

Therefore, I propose that when one creates a link or image through the toolbar (Ctrl+L / Ctrl+G), **the system should be able to escape at least the above mentioned characters**.