Allow filter list expiry time below 12 hours

[llaurenss]

Prerequisites

• I verified that this is not a filter list issue. Report any issues with filter lists or broken website functionality in the uAssets issue tracker.
• This is not a support issue or a question. For support, questions, or help, visit /r/uBlockOrigin.
• I performed a cursory search of the issue tracker to avoid opening a duplicate issue.
• The issue is not present after disabling uBO in the browser.
• I checked the documentation to understand that the issue I am reporting is not normal behavior.

I tried to reproduce the issue when...

• uBO is the only extension.
• uBO uses default lists and settings.
• using a new, unmodified browser profile.

Description

I wanted to self host a modified version of the quick fixes filter list with a more frequent updating interval. But it seems that setting the expiry time lower than 12 hours doesn't change anything and the filter list will still only expire after 12 hours.

A specific URL where the issue occurs.

/dashboard.html#3p-filters.html

Steps to Reproduce

1. Create a filter list
2. Set the expiry time to 1 hour or anything below 12 hours with the ! Expires: parameter
3. add the list to ublock origin
4. wait the given time and notice it won't be marked as outdated

Expected behavior

Would be great to see uBlock add support for expiry time below 12 hours even if this is just for custom lists

Actual behavior

Expiry time limited to a minimum of 12 hours.

uBO version

1.52.2

Browser name and version

Firefox 118.0.2

Operating System and version

Windows 10 19045.3570

[gothic-bum]

It is not an issue/bug, and it is normal behavior.

By design, 12 hours is the minimum value for the expires directive.

[llaurenss]

Now with the almost daily anti adblock updates by Youtube it would be nice to have the minimum value be lowered. So I'll try to rewrite it more as a feature request in that case.

[gothic-bum]

Lowering the value would place additional load on the serving infrastructure which is already dealing with bandwidth issues / limits.

[llaurenss]

I think you're misunderstanding me, I'm not asking to change the expiry time of the default filters, I can very well understand why that limit is in place for those. I'm asking for custom filters (hosted on my own server) to not have the same restrictions

[stephenhawk8054]

Previously, even with a shorter interval for external lists, users cannot get full abilities due to trusted filters not available for external lists.

However, with the development of trusted lists set by users here: #2895 (comment) , I think an advanced user can achieve shorter update interval of quick fix list without loading more requests to uBO repos:

• Fork and sync uAssets
• Auto set up Last modified and Expires time for the lists
• Add users' repo as a trusted source of lists
• Turn off uBO's quick fix and add users' own quick fix list (which needs to be synced frequently)

The only issue now is the Expires time (currently minimum is 12 hours)

---

I'm using a synced quick fix list as an example, it can apply to independent external lists too, in case users develop their own solutions.

[DandelionSprout]

I notice that this thread (except llaurens) only discusses the uAssets lists, whereas 3rd-party lists haven't been discussed at all. I'd be in favour of this kind of technical support, so that 3rd-party list makers can set lower times, even if I myself have yet to edit my lists to use any value lower than 1 day at the time of writing.

[gwarser]

Gorhill is working on this AdguardTeam/FiltersCompiler#192. So there is a huge chance that in next version you will be able to serve differential updates with much higher frequency.

[gwarser]

6 hours gorhill/uBlock@153783c

Differential updates gorhill/uBlock@d05ff8f#diff-bb0a23b7c8c08b99549300d4571ee50f0fcbb877eb8b84fb2d4c4c3ec1ffc1c4

---

4 hours gorhill/uBlock@2360bc0

[THEtomaso]

gorhill/uBlock@2360bc0

In uBO v1.54.0, ! Expires: Never now prevents filter lists from updating, even when forced.
Could this be a bug/side-effect caused by the above change, or is it by design?

Details/discussion here:
DandelionSprout/adfilt#779 (comment)

[gorhill]

The list does update, it's just always seen as out of date.

---

By the way, this list is unmaintained:

! Last modified: 2021-05-10 16:35:01

[THEtomaso]

OK, but in previous uBO versions, when forcing an update, the clock icon would appear regardlessly, simply indicating a succesfull update check.
In uBO v1.54.0, the out-of-date icon appears instead, resulting in an endless recheck.
In light of recent changes, which aims to lower uBO's number of requests and bandwidth usage, wouldn't its former behaviour be more appropriate for cases like this?
Some special / highly specific filter lists might not even need updating.
Also, it seems more logical (at least to me) that ! Expires: Never would declare the list always to be considered up-to-date!