Prevent usage of specific or all (default) canvas APIs.
Syntax
```text
example.com##+js(prevent-canvas [, contextType])
```
- `contextType`: A specific type of canvas API to prevent (default to all
APIs). Can be a string or regex which will be matched against the type
used in getContext() call. Prepend with `!` to test for no-match.
Examples
1. Prevent `example.com` from accessing all canvas APIs
```adblock
example.com##+js(prevent-canvas)
```
2. Prevent access to any flavor of WebGL API, everywhere
```adblock
*##+js(prevent-canvas, /webgl/)
```
3. Prevent `example.com` from accessing any flavor of canvas API except `2d`
```adblock
example.com##+js(prevent-canvas, !2d)
```
References
https://developer.mozilla.org/en-US/docs/Web/API/HTMLCanvasElement/getContext
To prepare for better compatibility with AdGuard's own `set-constant`
scriptlet.
The 3rd position parameter which dictates how to set the value has
been converted into a vararg paramater, as follow:
..., as, function
..., as, callback
..., as, resolved
..., as, rejected
Similarly, the parameter used to dictate when the scriptlet
should become effective is now to be used as a vararg:
..., runAt, load
Related issue:
https://github.com/uBlockOrigin/uBlock-issues/issues/2783
Ideally, AdGuard would support its `stack` parameter as a
vararg, to be discussed.
Related issue:
https://github.com/uBlockOrigin/uBlock-issues/issues/2773
The `randomize` paramater introduced in https://github.com/gorhill/uBlock/commit/418087de9c
is now named `directive`, and beside the `true` value which is meant
to respond with a random 10-character string, it can now take the
following value:
war:[web_accessible_resource name]
In order to mock the XHR response with a web accessible resource. For
example:
piquark6046.github.io##+js(no-xhr-if, adsbygoogle.js, war:googlesyndication_adsbygoogle.js)
Will cause the XHR performed by the webpage to resolve to the content
of `/web_accessible_resources/googlesyndication_adsbygoogle.js`.
Should the resource not exist, the empty string will be returned.
Now support AdGuard's `randomize` parameter. If `true`,
the scriplet will generate a random 10-character string
to be returned as the response.
Reference:
https://github.com/AdguardTeam/Scriptlets/blob/master/wiki/about-scriptlets.md#prevent-xhr
AdGuard's `prevent-xhr` also support `length:n-m` form,
but since I do not see it being used, for now it's not
supported in uBO's `no-xhr-if`.
Additionally, the scriptlet will now honor `responseType` and
return the proper response type accordingly.
`fetchPropsToMatch` is an optional variable argument. If provided,
the scriplet will take effect only when the JSON data is obtained
through `Response.json()` and if there is a match with the value of
`fetchPropsToMatch` and the properties of the `Response` instance.
Examples of usage:
...##+js(json-prune, ads, , , fetchPropsToMatch, ?param=)
...##+js(json-prune, ads, , , fetchPropsToMatch, url:?param= method:get)
The optional variable argument `fetchPropsToMatch` acts as an additional
narrowing condition to fulfill before the JSON data is pruned.
Specifically, the variable argument `log` can take one of three
values to enable logging mechanism:
..., log, match => log only when there is a match
..., log, nomatch => log only when there is no match
..., log, all => log unconditionally
Prepend pattern with `!` to test for unmatched patterns in
stack trace. This applies to sctiplet parameters which purpose
is to test against the stack, i.e. `aost` and `json-prune`.
Additionally, dropped support for JSON notation in favor of
optional variable arguments notation.
Related discussion:
- https://github.com/uBlockOrigin/uBlock-discussions/discussions/789#discussioncomment-6520330
This extends logging capabilities of `json-prune` scriptlet as
follow:
...##+js(json-prune, a, b, stackNeedle, log, [logneedle], logstack, 1)
Whereas before, the only way to log `json-prune` usage was to skip
providing the property chain:
...##+js(json-prune, , b)
Where `b` was the expression to filter out logging output.
With the extended logging capabilities, the logging output can
be filtered out with `logneedle`, which can be a regex literal.
Additionally, to log the stack trace the `stackNeedle` argument
must be set to non-empty string. You can use `/.^/` to log the
stack trace without matching it.
Related issue:
- https://github.com/AdguardTeam/Scriptlets/issues/332
Additionally, uBO's own scriplet syntax now also accept quoting
the parameters with either `'` or `"`. This can be used to avoid
having to escape commas when they are present in a parameter.
Related issue:
- https://github.com/uBlockOrigin/uAssets/issues/18725
Testing the context was causing the deprecated static property
RegExp.$1 to be clobbered, causing webpage breakage because this
property was subsequently used used by the caller.
New official name: `no-window-open-if`.
The pattern will now be matched against all arguments passed
to `window.open()`: all the arguments are joined as a single
space-spearated string, and the result is used as the target
for matching the pattern.
To enable logging, used the extra parameters approach, i.e.
`log, 1`, which should come after the positional arguments
`pattern`, `delay`, and `decoy`.
Added support for extra parameter `reload, 1`. If present,
the scriplet will force a reload of the webpage if the cookie
being set was not already set.
As per feedback from filter list maintainers.
The scriptlet remove the *whole* text of a DOM node. Usage:
example.com##+js(remote-node-text, nodeName, condition, ...)
Where `condition` is a pattern to find in the target node for the
removal to occur. Since the text of the node is wholly removed,
this is not a scriplet which requires a trusted-source, as it is
virtually a similar capability as removing DOM nodes through
procedural cosmetic operator `:remove()` (which can't target
`#text` nodes), which does not require trusted-source.
Alias: `rmnt`
The extra parameters are the same as those documented for
`replace-node-text`.
For consistency, the alias for `replace-node-text` has been renamed
`rpnt`.
When scriptlets can receive extra optional paramaters, these will
now be passed as pair of extra paramaters in the filter declaration,
whereas each pair is a `name, value` instance.
As a result, the optional paramaters that can be passed to the
`aeld` scriptlet can be passed this way, i.e. no longer need
a JSON approach, example:
github.com##+js(aeld, click, , log, 1)
github.com##+js(aeld, , , runAt, idle, log, 1)
The non-optional paramaters are always positional, after which
the optional paramaters are non-positional pairs of values.
Alias: `trusted-set`
Behaves exactly like set-constant, except that any arbitrary JSON-
compatible value can be set.
By default the value is treated as a string, which can be anything.
If the value starts with `{` and ends with `}`, the value will be
JSON-parsed, and the `value` property of the resulting object will
be used.
As with any scriptlet requiring trust, filters using
`trusted-set-constant` can only come from trusted filter lists,
otherwise they are discarded.
Related discussion:
- https://github.com/uBlockOrigin/uAssets/discussions/18185#discussioncomment-5977456
