If you encounter problems with QuickLook not creating Thumbnails or Previews properly, one of the first steps is to discover which code is responsible for generating those for QuickLook. Prior to macOS Sequoia, the standard way to do that was using the command tool qlmanage, among whose options is -m, to list all the qlgenerators available on your Mac. If you’ve tried that in Sequoia, you’ll surely have noticed that no longer works.

qlmanage

Since Catalina, Apple has been encouraging developers to switch away from qlgenerators to app extensions to create custom Thumbnails and Previews for QuickLook, and Sequoia is the first version of macOS that can’t use third-party qlgenerators. I have noticed some document types that only a few weeks ago in Sonoma still used custom thumbnails and full previews, but now can’t do so, although others continue to work normally.

These are controlled in the Quick Look item in Login Items & Extensions in General settings.

That should list all third-party app extensions providing this service, and enabling the right one(s) could fix some of those problems. But it turns out this list isn’t complete, and doesn’t in any case tell you which app extension handles which file type. For those, you’d normally turn to qlmanage, but its -m option can only see the qlgenerators in macOS, and no third-party app extensions at all. In fact, qlmanage is now of little help for anything related to QuickLook. I’ve gone back through Sonoma and Ventura, and qlmanage there is no different: although it does list third-party qlgenerators, none of those provided in app extensions appear in its list.

QuickLook app extensions

As far as I can discover, Apple doesn’t provide any equivalent of qlmanage that can report on QuickLook app extensions. The closest it comes is in the pluginkit tool, that can list all app extensions known to macOS. With a bit of tweaking, its -m option can reveal which of those use the QuickLook SDKs for Thumbnails or Previews.

Armed with the appex bundle path from pluginkit, you can then inspect the Info.plist in each, where there’s an array of QLSupportedContentTypes giving the UTIs of all file types supported by that appex. Although I’m sure someone could implement that in a shell script, this seemed an ideal task for my free utility Mints.

Mints and QuickLook

Version 1.20 of my free utility Mints is now available from here: mints120
from Downloads above, from its Product Page, and via its auto-update mechanism.

This adds a twenty-fifth button to the app’s control window, named QuickLook, at the bottom left. Click on that and Mints will open a new window and fill it with information about all the qlgenerators and QuickLook appexes your Mac knows about.

For qlgenerators, you’re given the file UTI, the path to the qlgenerator file, and (when available) its version number, e.g.
com.adobe.pdf /System/Library/QuickLook/PDF.qlgenerator (1002.2.3)

App extensions are divided into two, the first are those providing Previews, and the second those for Thumbnails, e.g.
com.apple.applescript.text /Applications/PreviewCode.app/Contents/PlugIns/Code Previewer.appex

This is an appex provided in one of Black Pyramid Software’s superb Preview series, in PreviewBundle 2 from the App Store (highly recommended).

You will see a few entries like Safari’s
[none] /System/Volumes/Preboot/Cryptexes/App/System/Applications/Safari.app/Contents/PlugIns/SafariQuickLookPreview.appex
with an appex that doesn’t have a list of file types in QLSupportedContentTypes.

Checking UTIs

It’s easy to guess which UTIs represent many file types, but some are a bit more cryptic. For those, copy and paste the UTI into the UTI field of my free UTIutility and it will give you clues as to its identity, including file extensions.

Unfortunately, some of the system qlgenerators support generic UTIs such as
public.audio /System/Library/QuickLook/Audio.qlgenerator (1002.2.3)
public.image /System/Library/QuickLook/Image.qlgenerator (1002.2.3)
public.movie /System/Library/QuickLook/Movie.qlgenerator (1002.2.3)
which clearly cover broad ranges of more specific file types, but don’t provide any more specific information.

How to identify QuickLook extensions

• List installed QuickLook extensions using Mints’ QuickLook button.
• Identify the file’s UTI using UTIutility.
• Locate the UTI in the list of extensions.
• If no match is found, check UTIs listed in UTIutility as Conforms.
• Check Quick Look item in Login Items & Extensions in General settings, to ensure that extension is enabled.

Next up for Mints is a feature to explore app extensions. I may be a little longer on that one.

QuickLook is the subsystem in macOS responsible for providing two types of document preview, small Thumbnails and full Previews. If you’ve already upgraded to Sequoia, you’ll have noticed that some document types are no longer displayed with their custom Thumbnails or Previews. This article explains what has happened, and how it should work in the future.

As I’ll detail on Saturday morning, QuickLook (or Quick Look) is the latest in a series of methods for providing custom icons and previews for documents, that started back in the initial versions of Classic Mac OS. macOS ships with its own code to generate Thumbnails and Previews for a wide range of standard file types, from text and PDF to audio and movies. To extend these to other types, developers are encouraged to provide their own code.

Prior to macoS 10.15 Catalina in 2019, the display of Thumbnails was supported by the QuickLook framework. From Catalina onwards, this is provided by a new framework named QuickLook Thumbnailing. The older framework is documented here, and had been deprecated for some years. Its replacement is documented here. To extend these, the older framework used QuickLook generators with the extension .qlgenerator, but in the newer framework this function is provided by QuickLook preview extensions, in particular Thumbnail Extensions, that were explained to developers at WWDC in 2019.

As with most deprecated features, eventually the time comes for Apple to remove support for the old, and for QuickLook generators that has occurred in macOS 15.0 Sequoia. From now on, QuickLook Generator plugins no longer work. Oddly, those provided by macOS in /System/Library/QuickLook are still named with the old extension of .qlgenerator, but all custom support now has to use the new framework in App Extensions.

To check whether an app is still trying to use an old QuickLook Generator, look inside the app bundle in Contents/Library/QuickLook. If you see one or more .qlgenerator bundles there, then those no longer work in Sequoia. Instead, you should see new Thumbnail Extensions in Contents/PlugIns, where you should see App Extension bundles with names ending in something like Thumbnail.appex and QuickLook.appex. Some of the better apps provide both QuickLook Generators for compatibility with Mojave and earlier, and App Extensions for more recent macOS.

If the app you rely on to generate custom QuickLook Thumbnails and Previews doesn’t yet come with those App Extensions, contact their Support and ask them when they’re going to implement the changes brought five years ago in Catalina. Particularly if you’re paying them a subscription, it’s time they caught up. Until they do, I’m afraid those Thumbnails and Previews simply won’t work in Sequoia, and you’ll continue to see generic icons rather than Thumbnails.

狡猾的细胞：癌症的进化故事与治愈之道

• 我们的身体是一个依赖多细胞合作运行的社会，而癌症就是其中的作弊细胞，它们拒绝合作，只会搭便车，利用和消耗公共资源满足的自己的私欲，无限繁殖，最终导致这个社会的崩溃。

• 我们身体的细胞一直处于一种博弈状态——父本基因和母本基因的博弈、细胞控制和细胞自由的博弈。一方面不能让细胞无限繁殖，另一方面又不能过度抑制细胞生长，唯有在两者之间达到一个微妙的平衡。

• 我们的生命之树上长满了癌症之果，只要细胞进行繁殖，就可能在演化的过程中出现变异，从而导致癌症。研究发现，生育更多的女性有更高的几率患癌。

• 为什么大象患癌的概率低而小白鼠患癌的概率高？这是不同物种的演化策略。大象体型更大、寿命更长，需要对癌症抑制投资更多资源，但同时也导致它们生长缓慢，繁殖能力弱，而小白鼠则相反。

• 对于癌细胞来说，我们的身体就是它们生存的生态系统，癌细胞在这个系统中进行演化，而我们则在地球生态系统中进行演化。面对人体的免疫系统和其他不利环境，癌细胞想要活下去并繁殖，虽然它们本身是作弊者，但也会产生合作，共同应对恶劣的生存环境。

• 适应性治疗不是要消灭癌症，而是随着肿瘤的变化相应调整治疗方案，简单来说，肿瘤扩散的时候加大用药，肿瘤稳定的时候减少用药甚至停药。对于无法彻底杀死的肿瘤来说，适应性治疗能降低因用药太多而演化出更恶性肿瘤的概率，让繁殖不那么快的肿瘤活着，就是对繁殖更快的恶性肿瘤的抑制。

猪八戒是哪八戒

• 解读《西游记》的小书，讲述神话人物的来历和佛道故事，分析命名和情节的寓意。我没看过原著，更没想过探究背后深意，只是闲读颇有意思。

• 《西游记》宣扬全真教的思想，主张三教合一，反对外丹，提倡内丹。一些人物的名字或外号其实就是炼丹的材料，比如红孩儿是铅、金鼻白猫老鼠精是水银。

• 《西游记》很讲究阶级差别，有后台的妖怪作乱终能平安无事，没有后台的大多横死。孙悟空自称妖怪的外公，也是一种划清阶级界限的说法，既占妖怪的便宜，又不能与妖怪关系太近。

• 《西游记》也有政治暗喻，车迟国讽嘉靖，乌鸡国除了是个王子复仇记，还影射朱祁镇和朱祁钰，宝象国又隐藏着朱棣、朱高炽和朱瞻基的历史，灭法国则揭露了和尚的腐败。

• 另外一些故事则引申到了恋爱、职场等话题：朱紫国国王是渣男，黄袍怪并不是真的爱老婆，小白龙是争夺继承权失败被贬，铁扇公主是失败的精英女性，观音是人力资源管理大师，白骨精是真正的草根事业型女性，等等。

コンビニ人間

• 惠子，一个从小脑回路就与众不同的人，为了不让父母伤心，开始隐藏自己的真实想法，但始终无法融入社会，用家人的话来说，就是“治不好”。

• 大学时在便利店打工，毕业后尝试找其他工作仍融入不了，还是继续在便利店打工，现在已经三十七岁，单身女性。便利店就是她的栖身之所。

• 休息日和朋友聚会，提到自己的现状，在别人眼中就是异类。

• 白羽是便利店新来的员工，但他来打工的目的是从顾客中找一个结婚对象。白羽认为现在社会和绳文时代没有区别，强大的男性可以任意挑选女性，对群体没有贡献的人就会被遗弃。

• 惠子看到被辞退的白羽无家可归，在便利店外觊觎女性顾客，请他到自己家住。

• 自己家里住了一个男人，只是把这个消息告诉妹妹，妹妹便激动坏了，自顾自话，说姐姐终于“治好了”。便利店的同事听到这个消息，也不再关心商品售卖，一味地谈起惠子的事。

• 妹妹来看望惠子，却发现惠子还是一如从前，哭了。白羽为惠子解围，假装他们是恋人关系，只是吵架了。

• 惠子辞了便利店的工作，人生没有了目标，连作息都不正常了，她的进食和休息，都是因便利店的工作所需。在白羽的陪同下，终于要去面试工作了，进到便利店，看到随意摆放的商品，一下子又恢复了身为便利店员工的本能。

• 面对生气的白羽，惠子说白羽对作为便利店员的她是不必要的东西。惠子的每个细胞都是为了便利店而运转，她要赶快找一个新的便利店工作。

• 有一份正经的工作、结婚生子，这是社会要求的普通、正常和规范。当惠子辞去便利店的工作后，她才真正意识到，便利店是自己真正的归属。

锌皮娃娃兵

• 入侵阿富汗的战争让苏联陷入泥淖，是其衰落和解体的重要原因之一，然而在我们的历史教科书上却没有对这场战争的描述。
• 他们怀着成为英雄或为国效力的理想奔赴战场，却成为这场不义战争中的施害者和受害者，要么身体的碎片被装进棺材，要么被视为犯下暴行的罪人回到祖国。

人慈：橫跨二十萬年的人性旅程，用更好的視角看待自己

• 将humankind译为人慈，既为该词的拆解式直译，又可切题，还谐音“仁慈”，当赞为妙笔。
• 作者为了宣扬“人性本善”，似乎走入了另一个极端，要彻底否认“人性本恶”。他立了几个典型的靶子——戈尔丁的《蝇王》、复活节岛的故事、霍布斯的《利维坦》以及几个经典的心理学实验（斯坦福监狱实验、电击实验、旁观者效应、破窗理论等）——然后再用个别案例和他人研究把这些靶子一一打倒。然而，作者列出的论据却并不是那么有说服力，而是陷入了以具体否定抽象的奇怪驳论境地。
• 为了否定《蝇王》，作者费劲千辛万苦在现实世界中找到了一个类似小说处境的真实故事，然后就说《蝇王》的故事在真实世界是不会出现的，只是戈尔丁恶意的想象，甚至以攻击戈尔丁的人格来证明自己的论点。对人性的解释难道也是数理逻辑吗，以一个反例驳倒一个命题。
• 复活节岛的历史研究是错误的，心理学实验是动了手脚和无良媒体推波助澜传播的。至于那些精心挑选的展现人类的和善、仁慈、友爱、宽恕和团结的动人故事，也可以有别的解释。这差不多就是作者的全部论据了。为什么有那么多证明“人性恶”的实验却少有证明“人性善”的实验呢？
• 作者想要宣扬“人性善”并没有问题，但为什么让全面否定“人性恶”的看法吗，妄图以一种宗教取代另一种宗教？当所有人都成了”人性善”教的教徒，世界就会充满爱与和平吗？
• 我不相信人性善，也不相信人性恶，我觉得先天的人性是空白的，是被后天的环境和教育染上了各种颜色。
• 这本书可以结合《人性实验》一起阅读，后者有前者所反驳的所有实验的介绍。

祈祷之海

• 讨论哲学、人性、自我和宗教的科幻小说。
• 科技和医学的进步会湮灭人性吗？
• 一种有趣的未来科技（能够取代人类大脑的宝石——恩多利装置）可见于不同的故事。
• 祈祷之海，是“我”从神的安慰中觉醒的故事。

白鳥の逃亡者

• 女主角是拉cello的天才高中少女，和已婚的指挥家有婚外情；男主角是杀死了妻子和她出轨对象的普通上班族。两人在车站的一次意外相撞，却演绎出了一段彼此安慰和救赎的故事。
• 无聊的小说，学日语的读物。

蝇王

• 事先知道了这是一个影响深远的故事，反而没有带来什么震撼。
• 译文佶屈聱牙，小说本身也有很多刻意的描写，读起来像是一部十八世纪或十九世纪早期的作品，不是很喜欢。
• 最后一章，拉尔夫逃避杰克一群人的追杀时，很有代入感，不自觉地让人紧张起来，为他捏一把汗。

大地上我们转瞬即逝的迅绚烂，是一本写给母亲的书，是一本自传。作者是越南移民，由母亲和外祖母抚养长大，书中带着歉意和爱意回忆着与母亲过往生活的点滴细节。为养家而被工作摧毁健康的母亲和她那对儿子时常带着粗暴的爱，体现出移民家庭在美国的生活之艰辛。外祖母对越南战争的回忆，提醒人们战争的伤痕永远无法消除。除了移民和越战元素，这本书也塑造了母亲和外祖母这两位勇敢而坚强的女性形象。

吉尔伽美什史诗，一部苏美尔英雄史诗，讲述了古代的王吉尔伽美什因好友恩启都遽死而意欲追求永生，历经千难万险却无功而返的故事。史诗中有大洪水的情节，应该是圣经大洪水的原版故事之一吧。

时代的喧嚣，是曼德施塔姆的自传、文论和书信的合集。自传讲述的重点不在自己，而是当时的社会环境和氛围，给人一种醉生梦死、穷奢极乐、风雨欲来的感觉。

重返天安門，是个人与六四的故事，有参与镇压的士兵，有受害者的母亲，有运动的学生领袖（离开的和留下的），也有未曾亲历的年轻一代。最后，还讲述了不为人知的成都屠杀事件。

青年变革者，是写梁启超的，通篇引用，看似旁征博引，实则枯燥至极。此书一点生气没有，一点己见没有，一点梁启超的魅力亦没有。烂书勿读。

死亡是一件孤独的事，装神弄鬼、莫名其妙的小说，除了名字一无是处。不要在这本书上浪费哪怕一分钟的时间，以我浪费了几个小时的经验之谈。