Slows down the page loading. A lot.
(about 4 or 5 times slower than other formatters). It's amazing how it is able to attract so many users.

Slows down sites to the point of being unusable. No read the manual section. Counterintuitive settings.

There are a lot of little bugs. Sometimes, I have to switch the extension off and on before it loads a side. Sometimes, when I add a site to my exceptions list it renders it as "dark" anyway. A lot of major sites (such as google.com) have parts of UI become invisible with this plug-in active (at least in dark mode). Kinda neat, but not up to the Chrome version yet.

Dark Mode - an extension I've been trying in this one's stead has a much smaller feature set but works far more reliably.

It really slowed down my browsing experience. It was so slow I had to uninstall. Looks like it works really well and has a lot of options. But this doesn't matter if it's too slow to use

Great idea but it makes pages slow. Needs to be addressed.

I want to like this add-on. I really do. I love everything else about it except it causes excessive loading times.

It's good on Chrome, but a disaster on Firefox. It integrates great with Facebook on Chrome, it's awful with FB on Firefox. Fix it before you release it. Cheers!

Good idea and i liked it. Mobil version seem better than Laptop version.
It slows the hell out of the PC! :S

Firefox becomes unusable as I only have 4 GB of RAM and it keeps freezing and is otherwise slow with this. Manjaro Linux OS. When disabling Firefox is normal again.
```bash
[jray@jr-dl ~]$ inxi -Fxz
System: Host: jr-dl Kernel: 4.19.2-1-MANJARO x86_64 bits: 64 compiler: gcc v: 8.2.1 Desktop: N/A Distro: Manjaro Linux
Machine: Type: Laptop System: Dell product: Latitude E6410 v: 0001 serial:
Mobo: Dell model: 0HNGW4 serial: UEFI: Dell v: A16 date: 12/05/2013
Battery: ID-1: BAT0 charge: 37.2 Wh condition: 37.2/48.8 Wh (76%) model: Samsung SDI DELL PT43699 status: Full
CPU: Topology: Dual Core model: Intel Core i5 M 560 bits: 64 type: MT MCP arch: Nehalem rev: 5 L2 cache: 3072 KiB
flags: lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 21290
Speed: 1197 MHz min/max: 1199/2667 MHz Core speeds (MHz): 1: 1325 2: 1200 3: 1320 4: 1442
Graphics: Device-1: Intel Core Processor Integrated Graphics vendor: Dell Latitude E6410 driver: i915 v: kernel
bus ID: 00:02.0
Display: x11 server: X.Org 1.20.3 driver: intel unloaded: modesetting resolution: 1440x900~60Hz, 1920x1080~60Hz
OpenGL: renderer: Mesa DRI Intel Ironlake Mobile v: 2.1 Mesa 18.2.5 direct render: Yes
Audio: Device-1: Intel 5 Series/3400 Series High Definition Audio vendor: Dell Latitude E6410 driver: snd_hda_intel
v: kernel bus ID: 00:1b.0
Sound Server: ALSA v: k4.19.2-1-MANJARO
Network: Device-1: Intel 82577LM Gigabit Network vendor: Dell Latitude E6410 driver: e1000e v: 3.2.6-k port: 7040
bus ID: 00:19.0
IF: eno1 state: up speed: 1000 Mbps duplex: full mac:
Device-2: Broadcom Limited BCM43224 802.11a/b/g/n vendor: Dell Wireless 1520 Half-size Mini PCIe Card driver: wl
v: kernel port: 7000 bus ID: 02:00.0
IF: wlp2s0 state: down mac:
Drives: Local Storage: total: 1.20 TiB used: 67.28 GiB (5.5%)
ID-1: /dev/sda vendor: Seagate model: ST9320423AS size: 298.09 GiB
ID-2: /dev/sdb type: USB vendor: Seagate model: Expansion size: 931.51 GiB
Partition: ID-1: / size: 284.06 GiB used: 19.33 GiB (6.8%) fs: ext4 dev: /dev/sda2
ID-2: swap-1 size: 8.18 GiB used: 1.67 GiB (20.4%) fs: swap dev: /dev/sda3
Sensors: System Temperatures: cpu: 49.0 C mobo: N/A sodimm: 43.0 C
Fan Speeds (RPM): cpu: 2901
Info: Processes: 202 Uptime: 7h 22m Memory: 3.72 GiB used: 2.22 GiB (59.9%) Init: systemd Compilers: gcc: 8.2.1
Shell: bash v: 4.4.23 inxi: 3.0.27
```

I must say this is by far the best looking extension I have ever used; but the performance is horrific, when loading specific websites it grinds your PC to a halt, and my computer is not a low spec machine.

i want to love it but it makes everything unbearably slow

Interferes with Firefox browser, not enough customization for prime time for me, and as everyone else mentioned, it slows performance.

Been using this for a while now, while it is one of the few that actually works, it slows down browsing by a LOT. PLEASE PLEASE fix this

The Firefox version makes using this thing so annoying. It's great under Chrome but for some reason it slows down load times so much it's impossible to use with Firefox.

I mean, it's a great idea and when it works it works well, but if I wanted to wait 5 seconds for each page to load I'd stop paying for my high speed cable connection. I gave up on Chrome after the latest update and wanted to move all my plugins over to Firefox. The is the only one that caused enough hassle that I had to give it up. Too bad I got so used to it under Chrome.

Awesome add-on but the Firefox version slows down a lot the browser. The Chrome version is perfect (but the browser isn't)

Es una muybuena extension, pero la eficacia de navegacion se ve reducida.

it makes Firefox hang and so slow

this is so close to being perfect.

websites look great but some are running slower and giving errors. i'll check back in a month or two to see if it has been updated!

Pages load extremely slow after installing this extension. Besides an ad blocker, I have no other extensions installed and I found that some pages wouldn't even load without a "stop script" pop-up.

I used to love it, but now its constantly breaking webpages. Things won't appear when they're right in front of you if you turn it off, images only load halfway, can't interact with some content on screen while Dark Reader is on...

I'm using Radeon Adrenaline drivers on Ryzen 2200g APU.

Looks promising, but interface is way too laggy (toggling or adjusting anything has a delay of a few seconds each time), should be able to click in adjustment bars (brightness, contrast, etc) to jump to an amount vs having to click the arrows over and over (made worse by the first issue), there's no option to automate based on time, and the search box on google.com is almost impossible to see (you would think such a major site would be flawless, much less not have such a huge visibility issue). Also causes significant lag with the whole browser (scrolling pages, switching tabs, etc), which is probably the cause of the first issue, and is by far the biggest problem, which makes the add-on completely unusable. The only saving grace is that the few sites I've checked with it seem to look good, with the exception of the Google search bar previously mentioned. With work, it could be a very nice extension, but it appears it will need a LOT of work. This is with Waterfox 56.1.0 x64 on Win10 x64.

Edit: The lag issue is tied to the use of the dynamic theme. Using static theme has no lag and seems to look mostly good as well. In fact, the Google search bar is more visible, but the sign in button is less visible. The apps button's visibility is poor with both.

I loved this extension on chrome and used to use it all the time. However, on Firefox, this thing absolutely shreds my CPU. When loading a new page or toggling the dark-mode on, it will spike to ~80% CPU usage for several seconds, and cause my entire browser to hang (note that this is on a 5th gen i7). I don't care for extensions that abuse my CPU power. This extension never used to be like this, but I've had to stop using it.