How do I modify an existing Firefox plugin?

Question

Delicious provide an excellent Firefox plugin for managing your bookmarks. However, they do not like the idea of people using Delicious as a private bookmark manager and so the "Mark as Private" checkbox option is set to "unchecked" by default.

As you can imagine, it gets pretty annoying having to check that box every single time I want to bookmark a page and, as Delicious have explicitly said they have no plan to support default checking as a setting, the only options are (1) tolerate it and (2) modify the plugin so the checkbox is checked by default.

The two places I've found that relate to the checkbox are both in the plugin's "chrome" file.

The first is:

    <checkbox id="cb_noShare" label="&addybookmarks.sharing.label;" accesskey="&addybookmarks.sharing.accesskey;"
     bk_tabindex="-1" oncommand="ybAddBkShare.removeTwitterFromSend();" style="-moz-user-focus: ignore !important;"/>

And the second is

< !ENTITY addybookmarks.sharing.label "Mark as Private"> < !ENTITY addybookmarks.sharing.accesskey "P"> < !ENTITY addybookmarks.sharing.tipHeader "Sharing"> < !ENTITY addybookmarks.sharing.tipContent "Check this option if you want this to be a private bookmark">

Unfortunately, though, making any changes to these causes ALL my plugins to not load, as though it were in safe mode.

What's going on and how can I get around it?

Many thanks

Answer 1

You should modify the checkbox element (the first entry in your question). You can make it checked by default by adding checked="true" as a new attribute to the tag:

<checkbox id="cb_noShare" label="&addybookmarks.sharing.label;"
accesskey="&addybookmarks.sharing.accesskey;" bk_tabindex="-1" oncommand="ybAddBkShare.removeTwitterFromSend();"
style="-moz-user-focus: ignore !important;" checked="true"/>

The other entry is the definition of XML entities. Instead of including the strings directly in the checkbox tag as the value of the label attribute, it's good practice to define an XML entity and use the entity instead. This allows for translating the extension in multiple languages depending and having Firefox show the text in the proper language depending on the user locale.