[DNSB]

I tried downloading the first book in your list using the latest update to FFF from the URL: "https://archiveofourown.org/works/44936056/" dumping the "navigate'(525" from the posted link and it worked without any problems. Your next two URLs point to the AO3 login page so aren't much use for testing.

This may not be much help to you since we are using different computer, ISPs, etc.

Spoiler:

Download 1 FanFiction Book(s) for archiveofourown.org
FFF: INFO: 2026-03-02 12:02:02,191: calibre_plugins.fanficfare_plugin.jobs(39): FanFicFare v4.55.0
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FFF: INFO: 2026-03-02 12:02:03,241: calibre_plugins.fanficfare_plugin.jobs(146): 

-------------------------------------------------------------------------------- https://archiveofourown.org/works/44936056
FFF: DEBUG: 2026-03-02 12:02:03,241: configurable.py(560): config site:archiveofourown.org
FFF: DEBUG: 2026-03-02 12:02:03,252: configurable.py(1036): use_browser_cache:
FFF: DEBUG: 2026-03-02 12:02:03,253: configurable.py(1057): use_basic_cache:true
FFF: INFO: 2026-03-02 12:02:03,253: base_otw_adapter.py(193): url: https://archiveofourown.org/works/44936056/navigate
FFF: INFO: 2026-03-02 12:02:03,253: base_otw_adapter.py(194): metaurl: https://archiveofourown.org/works/44936056
FFF: DEBUG: 2026-03-02 12:02:03,253: cache_basic.py(117): 
========== HIT (GET) BasicCache
https://archiveofourown.org/works/44936056/navigate
FFF: DEBUG: 2026-03-02 12:02:03,254: requestable.py(55): Encoding:utf8
FFF: DEBUG: 2026-03-02 12:02:03,254: cache_basic.py(117): 
========== HIT (GET) BasicCache
https://archiveofourown.org/works/44936056
FFF: DEBUG: 2026-03-02 12:02:03,254: requestable.py(55): Encoding:utf8
FFF: DEBUG: 2026-03-02 12:02:03,316: base_otw_adapter.py(323): numChapters: ()
FFF: DEBUG: 2026-03-02 12:02:03,329: calibre_plugins.fanficfare_plugin.jobs(199): metadata newforanthology:
FFF: INFO: 2026-03-02 12:02:03,333: calibre_plugins.fanficfare_plugin.jobs(247): write to C:\Users\<user>\AppData\Local\Temp\calibre-w4sjxdn4\fanficfare_lis8_s_q\Wouldn't Trade This Life For Diamonds Or Jewels-ashilrak-mqmko2vf.epub
FFF: INFO: 2026-03-02 12:02:03,334: base_writer.py(197): Save directly to file: C:\Users\<user>\AppData\Local\Temp\calibre-w4sjxdn4\fanficfare_lis8_s_q\Wouldn't Trade This Life For Diamonds Or Jewels-ashilrak-mqmko2vf.epub
FFF: DEBUG: 2026-03-02 12:02:03,335: base_otw_adapter.py(485): Getting chapter text for: https://archiveofourown.org/works/44...ters/113067076 index: 0
FFF: DEBUG: 2026-03-02 12:02:03,336: cache_basic.py(117): 
========== MISS (GET) BasicCache
https://archiveofourown.org/works/44...ters/113067076
FFF: DEBUG: 2026-03-02 12:02:03,336: fetcher_requests.py(114): 
---------- REQ (GET) RequestsFetcher
https://archiveofourown.org/works/44...ters/113067076
FFF: DEBUG: 2026-03-02 12:02:08,758: fetcher_requests.py(127): response code:200
FFF: DEBUG: 2026-03-02 12:02:08,758: decorators.py(118): fromcache:False
FFF: DEBUG: 2026-03-02 12:02:08,758: decorators.py(129): random sleep(2.00-6.00):3.20
FFF: DEBUG: 2026-03-02 12:02:11,959: requestable.py(55): Encoding:utf8
FFF: INFO: 2026-03-02 12:02:12,020: writer_epub.py(411): Saving EPUB Version 2.0
FFF: INFO: 2026-03-02 12:02:12,131: calibre_plugins.fanficfare_plugin.jobs(77): 
Download Results:
Add https://archiveofourown.org/works/44936056 Download epub completed, 1 chapters.

FFF: INFO: 2026-03-02 12:02:12,131: calibre_plugins.fanficfare_plugin.jobs(102): 
Add
https://archiveofourown.org/works/44936056