The procedural cosmetic filtering code has been split from
the content script code injected unconditionally and will
from now on be injected only when it is needed, i.e. when
there are procedural cosmetic filters to enforce.
The motivation for this is:
https://www.debugbear.com/blog/2020-chrome-extension-performance-report#what-can-extension-developers-do-to-keep-their-extensions-fast
Though uBO's content script injected unconditionally in all
pages/frames is relatively small, I still wanted to further
reduce the amount of content script code injected
unconditionally: The procedural cosmetic filtering code
represents roughly 14KB of code the browser won't have to
parse/execute unconditionally unless there exists procedural
cosmetic filters to enforce for a page or frame.
At the time the above article was published, the total
size of unconditional content scripts injected by uBO was
~101 KB, while after this commit, the total size will be
~57 KB (keeping in mind uBO does not minify and does not
remove comments from its JavaScript code).
Additionally, some refactoring on how user stylesheets are
injected so as to ensure that `:style`-based procedural
filters which are essentially declarative are injected
earlier along with plain, non-procedural cosmetic filters.
This should improve usability of uBO's hard-mode
and "relax blocking mode" operations. This is the
new default behavior.
The previous behavior of forcing a reload of the
page can be re-enabled by simply setting the `3p`
bit of the advanced setting `blockingProfiles`
to 1.
Related issues:
- https://github.com/gorhill/uBlock/issues/1390
- https://github.com/gorhill/uBlock/issues/2334
The deadline to interactively load a specific media
element has been extended from 2sec to 5sec.
Clicking over a blocked large media element will cause
uBO to lookup and handle all potentially blocked large
elements at the cursor position. This should take care
of being able to unblock media elements hidden under
other DOM object.
The CSS style applied to blocked large media elements
has been fine tuned to improve interactivity.
uBO will now remember the specific media elements which
were unblocked and keep them exempted from being
further blocked. This would be an issue when unblocking
a video and then a bit later seeking to another point
in the video, in which case uBO would again block
network requests for that video.
The specificity slider will now be more intuitive
by ordering candidates by match count from highest
match count to the left to the lowest match count
to the right.
Candidates with same match counts will be discarded
and replaced with the shortest candidate.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/763
Changes:
From now on, uBO will allow click-to-subscribe on only
a few select domains, currently:
- https://filterlists.com/
- https://github.com/
- https://github.io/
More domains can be added if and only the demonstration
is made that more than a marginal number of filter lists
can be subscribed from those domains.
The browser alert box is no longer used to confirm
subscription to a filter list. Instead, the asset
viewer has been expanded to serve that purpose. This
way, users can peruse at the content of a filter list
before subscribing to it.
Further iterating on the work done in following commit:
- 1268f0ae43
This commit adds a new widget to the element picker to
control the depth of a cosmetic filter selector. The
new widget is essentially just another way of selecting
the depth, which is still controllable through picking
one of the cosmetic filters in the list of candidates.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/851
The ctrl key is no longer used to adjust specificity of
a candidate filter.
A new widget has been added to adjust the specificity of
a candidate filter to various level. The widget will be
visible as long as the candidate filter matches one entry
in the list of suggested candidate cosmetic filters.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/1226
Related commit:
- 9eb455ab5e
In the previous commit, the element picker dialog was
isolated from the page content. This commit is to also
isolate the svg layers from the page content.
With this commit, there is no longer a need for an anonymous
iframe and the isolated world iframe is now directly
embedded in the page.
As a result, pages are now unable to interfere with any
of the element picker user interface. Pages can now only
see an iframe, but are unable to see the content of that
iframe. The styles applied to the iframe are from a user
stylesheet, so as to ensure pages can't override the
iframe's style properties set by uBO.
Regression from:
- 16727d68c8
The issue was causing the element picker to being
unable to select elements with no valid `srcset`
property.
Test case -- trying to select one of the embedded
frames in the following page would fail:
- http://raymondhill.net/ublock/tiles1.html
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/1071
Additionally, match unconditionally against `srcset` attribute
when trying to find matching elements in the page. For example,
sometimes an img element may set both `src` and `srcset`
properties, they should not be deemed mutually exclusive.
This commit moves some of the parsing logic of static
extended filtering into the static filtering parser; this
allows better syntax highlighting and creation-time
error-catching for cosmetic, HTML, and scriptlet filters.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/974
Related feedback:
- https://www.reddit.com/r/uBlockOrigin/comments/fuscia/
The race condition was that a content script could
query the main process to retrieve cosmetic filters
while the cosmetic filters had not been yet fully
loaded into memory. The fix ensure that an already
injected content script will re-query once the
cosmetic filters are fully loaded in memory at
browser launch time.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/923
Use current page's hostname instead of that of
image URLs to decide whether to reset pattern
union with previous picker sessions.
The fixed issue arose from the fact that the
page uses URLs from different origins in a
single srcset attribute.
***
New procedural cosmetic operator: `:remove()`
Related issue:
- https://github.com/gorhill/uBlock/issues/2252
The purpose is to outright remove elements from the
DOM tree. Since `:remove()` is an "action" operator,
it must only be used as a trailing operator (just
like the `:style()` operator).
AdGuard's cosmetic filter syntax `{ remove: true; }`
will be converted to uBO's `:remove()` operator
internally.
***
New procedural cosmetic operator: `:upward(...)`
The purpose is to lookup an ancestor element.
When used with an integer argument, it is synonym of
`:nth-ancestor()`, which will be deprecated and which
will no longer be supported once no longer used in
mainstream filter lists.
Filter lists maintainers must only use `:upward(int)`
instead of `:nth-ancestor(int)` once the new operator
become available in all stable releases of uBO.
`:upward()` can also accept a CSS selector as argument,
in which case the nearest ancestor which matches the
CSS selector will be selected.
Override the Backspace key, not just the Delete key, as Mac keyboards have Backspace as the only delete key and label it Delete.
Source of key value: https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/key/Key_Values#Editing_keys
More background on Mac keyboard shortcuts: Mac keyboards can emulate Delete using fn+Delete, meaning Forward Delete, but Mac software does not use it except in text editing. When deletion is dangerous, Mac software requires holding a modifier key in conjuction with Delete, but I think it’s better to make deletion easy in this case.
This new binding has a potential downside: if the user Backspace key normally goes Back in history (which can differ across OSs and browsers), this will change the behavior to delete the selected element instead. If the user really wants to go back in history, they will have to press Escape to leave the mode and then press Backspace, or they will have to press an alternative keyboard shortcuts such as Alt+Left. I think the user will rarely want to go back in history in the middle of picking an element, though.
That downside could be mitigated by conditioning the key check on `runtime.PlatformOs` (https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/runtime/PlatformOs). But that would complicate the code a lot compared to the importance of this feature, and such detection would still fail to capture the user’s intent accurately in all cases. I think it’s better to unconditionally accept both Backspace (Delete) and Delete (Forward Delete).
