Improve content injection algorithm

[confessor-adguard]

Total content injection algorithm reworking.

First and foremost, this should solve issues with document-start userscripts, resolve some of the known conflicts (AdsBypasser, YouTube+), and also optimize usage of ad blocker scripts and styles.

[BooBerry]

Will this also address the issue posted in this topic today?

https://forum.adguard.com/index.php?threads/jquerify.11361/

[ameshkov]

@confessor-adguard some notes on this:

1. You currently wrap every JS rule into a try-catch statement. It would be better if you have on try-catch statement for all rules.
2. It makes sense execute JS rules from an anonymous function:

(function() {
    try {
       JS rules go here
    } catch (ex) {
        // handle errors    
    }
})();

1. We should implement some simple and lightweight jquery-like api functions to be used inside the JS rules. Like AG_onLoad and such. Let's ask @Alex-302 which functions do he need in this API.

As I understand here is a list of must-have functions.

1. window load handler (like AG_onLoad)

$(function() { /* here goes the code */ });

2. simple function to remove elements by selector:

$('someelement').remove();

3. closest parent selector:

$('element').closest('div')

4. children selector:

$('element').find('selector')

Just to give you an idea:
https://github.com/finom/balalaika

[ameshkov]

@confessor-adguard improve userscripts:

1. Add comments to the important functions
2. Change naming (no underscores)
3. Do not copy deprecated properties (like those with webkit* prefix)

[BooBerry]

Is there any Greasemonkey metadata blocks that Adguard doesn't support yet, where it could also be improved for compatibility reasons? Example being @run-at document-idle which was introduced in Greasemonkey 3.6. There's also Chrome/Safari-specific changes in the Tampermonkey API to look over and consider, I'm thinking.

[ameshkov]

@BooBerry nice, thanks for noting these!

[ameshkov]

@confessor-adguard please note that in IE10 the limits situation has changed.

The limits were increased in IE 10 to the following:

A sheet may contain up to 65534 rules
A document may use up to 4095 stylesheets
@import nesting is limited to 4095 levels (due to the 4095 stylesheet limit)

We should take this into account.