There's a number of faux pas you can commit when using [% terms.Bugzilla %]. At the very least, these will make Mozilla contributors upset at you; if committed enough times they will cause those contributors to demand the disabling of your [% terms.Bugzilla %] account. So, ignore this advice at your peril.

That said, Mozilla developers are generally a friendly bunch, and will be friendly towards you as long as you follow these guidelines.

1. Commenting

This is the most important section.

1. No pointless comments. Unless you have something constructive and helpful to say, do not add a comment to a [% terms.bug %]. In [% terms.bugs %] where there is a heated debate going on, you should be even more inclined not to add a comment. Unless you have something new to contribute, then the [% terms.bug %] owner is aware of all the issues, and will make a judgement as to what to do. If you agree the [% terms.bug %] should be fixed, vote for it. Additional "I see this too" or "It works for me" comments are unnecessary unless they are on a different platform or a significantly different build. Constructive and helpful thoughts unrelated to the topic of the [% terms.bug %] should go in the appropriate newsgroup.
2. No obligation. "Open Source" is not the same as "the developers must do my bidding." Everyone here wants to help, but the only person who has any obligation to fix the [% terms.bugs %] you want fixed is you. Therefore, you should not act as if you expect someone to fix a [% terms.bug %] by a particular date or release. Aggressive or repeated demands will not be received well and will almost certainly diminish the impact and interest in your suggestions.
3. No abusing people. Constant and intense critique is one of the reasons we build great products. It's harder to fall into group-think if there is always a healthy amount of dissent. We want to encourage vibrant debate inside of the Mozilla community, we want you to disagree with us, and we want you to effectively argue your case. However, we require that in the process, you attack things, not people. Examples of things include: interfaces, algorithms, and schedules. Examples of people include: developers, designers and users. Attacking a person may result in you being banned from [% terms.Bugzilla %].
4. No private email. Unless the [% terms.bug %] owner or another respected project contributor has asked you to email them with specific information, please place all information relating to [% terms.bugs %] in the [% terms.bug %] itself. Do not send them by private email; no-one else can read them if you do that, and they'll probably just get ignored. If a file is too big for [% terms.Bugzilla %], add a comment giving the file size and contents and ask what to do.

2. Changing Fields

1. No messing with other people's [% terms.bugs %]. Unless you are the [% terms.bug %] assignee, or have some say over the use of their time, never change the Priority or Target Milestone fields. If in doubt, do not change the fields of [% terms.bugs %] you do not own - add a comment instead, suggesting the change.
2. No whining about decisions. If a respected project contributor has marked a [% terms.bug %] as INVALID, then it is invalid. Someone filing another duplicate of it does not change this. Unless you have further important evidence, do not post a comment arguing that an INVALID or WONTFIX [% terms.bug %] should be reopened.

3. Applicability

1. Some of these rules may not apply to you. If they do not, you will know exactly which ones do not, and why they do not apply. If you are not sure, then they definitely all apply to you.

If you see someone not following these rules, the first step is, as an exception to guideline 1.4, to make them aware of this document by private mail. Flaming people publically in [% terms.bugs %] violates guidelines 1.1 and 1.3. In the case of persistent offending you should report the matter to Gerv.

This entire document can be summed up in one sentence: do unto others as you would have them do unto you.

Other useful documents: The [% terms.Bug %] Writing Guidelines.