New square corners bugs & non-working square checkboxes

### Describe the bug

I found new areas where square corners don't work or are glitched.

Yes, checkboxes aren't square even when I enabled the `userChrome.rounding.square_checklabel` value in the `about:config` (except for the page info window where `userChrome.rounding.square_checklabel` works as intended).

I know, that I should have initially created a new issue for the square checkboxes bug, but I would keep it united since I already mentioned this issue on #908.

And again, I put all of these bugs into one single issue report to avoid issue tracker cluttering.

----------

#### List of features & areas which doesn't support square corners:

- [ ] The reader panel
- [ ] Two reader menus
- [ ] Buttons in the Pocket pop-up
- [ ] Two bubbles on the "Add password" page
- [ ] Upper & bottom corners of `about:config` content
- [ ] Two content tables in the page info window
- [ ] Corners of tables in `about:protections`
- [ ] New tab page tiles & their outlines
- [ ] Address bar tags labels
- [ ] Beta features labels
- [ ] Blue translated language label in the address bar
- [ ] Extensions events counter label
- [ ] Extensions recommendations infobox
- [ ] The bottom corners of `about:certificate` page content
- [ ] Website tooltips
- [ ] Buttons & fields in the screenshot tool area
- [ ] Firefox Mobile infobox in "More from Mozilla"
- [ ] Firefox Nightly Labs page content corners (Nightly only)
- [ ] Firefox Experimental sidebar gear menu content boxes (Nightly only)
- [ ] Several buttons in the new reader flyouts (From v129.0.0)
- [ ] Protections Dashboard statistics pillars bars
- [ ] The square corner frame around the experimental sidebar gear menu stopped working (Nightly only)
- [ ] The location field in the "Add Security Exception" window
- [ ] The fullscreen indicator pop-up
- [ ] The NTP search results pop-up
- [ ] The Pdf.js annotation edit menu
- [ ] The Pdf.js add image preview dialogue
- [ ] Empty recent activity frame
- [ ] Recent activity cards
- [ ] Recommended stories cards
- [ ] The Chatbot selection dialogue in the sidebar (Nightly only)
- [ ] The tall news widget in about:home page (Nightly only)

#### List of features & areas which may be categorised as square corners bugs, but may not (depending on the main developer's decision):

- [ ] Reader mode font settings counters
- [ ] Icon/Colour selectors in the "Add New Container" & "Container Settings" dialogues

**NOTE:** All issues are sorted from oldest to newest mentioned.

### Expected behavior

_No response_

### Screenshots

#### The reader panel isn't supporting square corners:

----------

#### Reader menu 1 isn't supporting square corners:

----------

#### Reader menu 2 isn't supporting square corners:

----------

#### Buttons in the pocket pop-up aren't supporting square corners:

----------

#### Password bubble 1 isn't supporting square corners:

----------

#### Password bubble 2 isn't supporting square corners:

----------

#### Upper & bottom corners of tables in about:config aren't square:

----------

#### Square checkboxes aren't working anywhere:
(Except for the page info window)


### OS

Windows 10

### OS - Others

_No response_

### Firefox Version

v127.0.0 (64-bit)

### Distribution

- [X] [Original Lepton](https://github.com/black7375/Firefox-UI-Fix)
- [ ] [Lepton's photon style](https://github.com/black7375/Firefox-UI-Fix/tree/photon-style)
- [ ] [Lepton's proton style](https://github.com/black7375/Firefox-UI-Fix/tree/proton-style)

### Theme

- [X] Light
- [X] Dark
- [ ] Alpenglow (System: Light)
- [ ] Alpenglow (System: Dark)
- [ ] System Default
- [ ] Others: (e.g. [Photon Colors](https://addons.mozilla.org/en-US/firefox/addon/photon-colors/), [Google Chrome Dark](https://addons.mozilla.org/en-US/firefox/addon/google-chrome-dark/), [Fairytale Of Nature](https://addons.mozilla.org/en-US/firefox/addon/fairytale-of-nature/))

### Theme - More Info

_No response_

### `user.js` setup

user.js setup

```javascript
// ** Theme Default Options ****************************************************
// userchrome.css usercontent.css activate
user_pref("toolkit.legacyUserProfileCustomizations.stylesheets", true);

// Fill SVG Color
user_pref("svg.context-properties.content.enabled", true);

// Restore Compact Mode - 89 Above
user_pref("browser.compactmode.show", true);

// about:home Search Bar - 89 Above
user_pref("browser.newtabpage.activity-stream.improvesearch.handoffToAwesomebar", false);

// CSS's `:has()` selector #457 - 103 Above
user_pref("layout.css.has-selector.enabled", true);

// Browser Theme Based Scheme - Will be activate 95 Above
// user_pref("layout.css.prefers-color-scheme.content-override", 3);

// ** Theme Related Options ****************************************************
// == Theme Distribution Settings ==============================================
// The rows that are located continuously must be changed `true`/`false` explicitly because there is a collision.
// https://github.com/black7375/Firefox-UI-Fix/wiki/Options#important
user_pref("userChrome.tab.connect_to_window", true); // Original, Photon
user_pref("userChrome.tab.color_like_toolbar", true); // Original, Photon

user_pref("userChrome.tab.lepton_like_padding", true); // Original
user_pref("userChrome.tab.photon_like_padding", false); // Photon

user_pref("userChrome.tab.dynamic_separator", true); // Original, Proton
user_pref("userChrome.tab.static_separator", false); // Photon
user_pref("userChrome.tab.static_separator.selected_accent", false); // Just option
user_pref("userChrome.tab.bar_separator", false); // Just option

user_pref("userChrome.tab.newtab_button_like_tab", true); // Original
user_pref("userChrome.tab.newtab_button_smaller", false); // Photon
user_pref("userChrome.tab.newtab_button_proton", false); // Proton

user_pref("userChrome.icon.panel_full", true); // Original, Proton
user_pref("userChrome.icon.panel_photon", false); // Photon

// Original Only
user_pref("userChrome.tab.box_shadow", true);
user_pref("userChrome.tab.bottom_rounded_corner", true);

// Photon Only
user_pref("userChrome.tab.photon_like_contextline", false);
user_pref("userChrome.rounding.square_tab", false);

// == Theme Compatibility Settings =============================================
// user_pref("userChrome.compatibility.accent_color", true); // Firefox v103 Below
// user_pref("userChrome.compatibility.covered_header_image", true);
// user_pref("userChrome.compatibility.panel_cutoff", true);
// user_pref("userChrome.compatibility.navbar_top_border", true);
// user_pref("userChrome.compatibility.dynamic_separator", true); // Need dynamic_separator

// user_pref("userChrome.compatibility.os.linux_non_native_titlebar_button", true);
// user_pref("userChrome.compatibility.os.windows_maximized", true);
// user_pref("userChrome.compatibility.os.win11", true);

// == Theme Custom Settings ====================================================
// -- User Chrome --------------------------------------------------------------
// user_pref("userChrome.theme.private", true);
// user_pref("userChrome.theme.proton_color.dark_blue_accent", true);
// user_pref("userChrome.theme.monospace", true);
// user_pref("userChrome.theme.transparent.frame", true);
// user_pref("userChrome.theme.transparent.menu", true);
// user_pref("userChrome.theme.transparent.panel", true);
// user_pref("userChrome.theme.non_native_menu", true); // only for linux

// user_pref("userChrome.decoration.disable_panel_animate", true);
// user_pref("userChrome.decoration.disable_sidebar_animate", true);
// user_pref("userChrome.decoration.panel_button_separator", true);
// user_pref("userChrome.decoration.panel_arrow", true);

// user_pref("userChrome.autohide.tab", true);
// user_pref("userChrome.autohide.tab.opacity", true);
// user_pref("userChrome.autohide.tab.blur", true);
// user_pref("userChrome.autohide.tabbar", true);
// user_pref("userChrome.autohide.navbar", true);
// user_pref("userChrome.autohide.bookmarkbar", true);
// user_pref("userChrome.autohide.sidebar", true);
// user_pref("userChrome.autohide.fill_urlbar", true);
// user_pref("userChrome.autohide.back_button", true);
// user_pref("userChrome.autohide.forward_button", true);
// user_pref("userChrome.autohide.page_action", true);
// user_pref("userChrome.autohide.toolbar_overlap", true);
// user_pref("userChrome.autohide.toolbar_overlap.allow_layout_shift", true);

// user_pref("userChrome.hidden.tab_icon", true);
// user_pref("userChrome.hidden.tab_icon.always", true);
// user_pref("userChrome.hidden.tabbar", true);
// user_pref("userChrome.hidden.navbar", true);
// user_pref("userChrome.hidden.private_indicator", true);
// user_pref("userChrome.hidden.titlebar_container", true);
// user_pref("userChrome.hidden.sidebar_header", true);
// user_pref("userChrome.hidden.sidebar_header.vertical_tab_only", true);
// user_pref("userChrome.hidden.urlbar_iconbox", true);
// user_pref("userChrome.hidden.urlbar_iconbox.label_only", true);
// user_pref("userChrome.hidden.bookmarkbar_icon", true);
// user_pref("userChrome.hidden.bookmarkbar_label", true);
// user_pref("userChrome.hidden.disabled_menu", true);

// user_pref("userChrome.centered.tab", true);
// user_pref("userChrome.centered.tab.label", true);
// user_pref("userChrome.centered.urlbar", true);
// user_pref("userChrome.centered.bookmarkbar", true);

// user_pref("userChrome.counter.tab", true);
// user_pref("userChrome.counter.bookmark_menu", true);

// user_pref("userChrome.combined.nav_button", true);
// user_pref("userChrome.combined.nav_button.home_button", true);
// user_pref("userChrome.combined.urlbar.nav_button", true);
// user_pref("userChrome.combined.urlbar.home_button", true);
// user_pref("userChrome.combined.urlbar.reload_button", true);
// user_pref("userChrome.combined.sub_button.none_background", true);
// user_pref("userChrome.combined.sub_button.as_normal", true);

// user_pref("userChrome.rounding.square_button", true);
// user_pref("userChrome.rounding.square_dialog", true);
// user_pref("userChrome.rounding.square_panel", true);
// user_pref("userChrome.rounding.square_panelitem", true);
// user_pref("userChrome.rounding.square_menupopup", true);
// user_pref("userChrome.rounding.square_menuitem", true);
// user_pref("userChrome.rounding.square_infobox", true);
// user_pref("userChrome.rounding.square_toolbar", true);
// user_pref("userChrome.rounding.square_field", true);
// user_pref("userChrome.rounding.square_urlView_item", true);
// user_pref("userChrome.rounding.square_checklabel", true);

// user_pref("userChrome.padding.first_tab", true);
// user_pref("userChrome.padding.first_tab.always", true);
// user_pref("userChrome.padding.drag_space", true);
// user_pref("userChrome.padding.drag_space.maximized", true);

// user_pref("userChrome.padding.toolbar_button.compact", true);
// user_pref("userChrome.padding.menu_compact", true);
// user_pref("userChrome.padding.bookmark_menu.compact", true);
// user_pref("userChrome.padding.urlView_expanding", true);
// user_pref("userChrome.padding.urlView_result", true);
// user_pref("userChrome.padding.panel_header", true);

// user_pref("userChrome.urlbar.iconbox_with_separator", true);

// user_pref("userChrome.urlView.as_commandbar", true);
// user_pref("userChrome.urlView.full_width_padding", true);
// user_pref("userChrome.urlView.always_show_page_actions", true);
// user_pref("userChrome.urlView.move_icon_to_left", true);
// user_pref("userChrome.urlView.go_button_when_typing", true);
// user_pref("userChrome.urlView.focus_item_border", true);

// user_pref("userChrome.tabbar.as_titlebar", true);
// user_pref("userChrome.tabbar.fill_width", true);
// user_pref("userChrome.tabbar.multi_row", true);
// user_pref("userChrome.tabbar.unscroll", true);
// user_pref("userChrome.tabbar.on_bottom", true);
// user_pref("userChrome.tabbar.on_bottom.above_bookmark", true); // Need on_bottom
// user_pref("userChrome.tabbar.on_bottom.menubar_on_top", true); // Need on_bottom
// user_pref("userChrome.tabbar.on_bottom.hidden_single_tab", true); // Need on_bottom
// user_pref("userChrome.tabbar.one_liner", true);
// user_pref("userChrome.tabbar.one_liner.combine_navbar", true); // Need one_liner
// user_pref("userChrome.tabbar.one_liner.tabbar_first", true); // Need one_liner
// user_pref("userChrome.tabbar.one_liner.responsive", true); // Need one_liner

// user_pref("userChrome.tab.bottom_rounded_corner.all", true);
// user_pref("userChrome.tab.bottom_rounded_corner.australis", true);
// user_pref("userChrome.tab.bottom_rounded_corner.edge", true);
// user_pref("userChrome.tab.bottom_rounded_corner.chrome", true);
// user_pref("userChrome.tab.bottom_rounded_corner.chrome_legacy", true);
// user_pref("userChrome.tab.bottom_rounded_corner.wave", true);
// user_pref("userChrome.tab.always_show_tab_icon", true);
// user_pref("userChrome.tab.close_button_at_pinned", true);
// user_pref("userChrome.tab.close_button_at_pinned.always", true);
// user_pref("userChrome.tab.close_button_at_pinned.background", true);
// user_pref("userChrome.tab.close_button_at_hover.always", true); // Need close_button_at_hover
// user_pref("userChrome.tab.close_button_at_hover.with_selected", true); // Need close_button_at_hover
// user_pref("userChrome.tab.sound_show_label", true); // Need remove sound_hide_label
// user_pref("userChrome.tab.container.on_top", true);
// user_pref("userChrome.tab.container.always_long", true);
// user_pref("userChrome.tab.sound_with_favicons.on_center", true);
// user_pref("userChrome.tab.selected_bold", true);

// user_pref("userChrome.navbar.as_sidebar", true);

// user_pref("userChrome.bookmarkbar.multi_row", true);

// user_pref("userChrome.findbar.floating_on_top", true);

// user_pref("userChrome.panel.remove_strip", true);
// user_pref("userChrome.panel.full_width_separator", true);
// user_pref("userChrome.panel.full_width_padding", true);

// user_pref("userChrome.sidebar.overlap", true);

// user_pref("userChrome.icon.disabled", true);
// user_pref("userChrome.icon.account_image_to_right", true);
// user_pref("userChrome.icon.account_label_to_right", true);
// user_pref("userChrome.icon.menu.full", true);
// user_pref("userChrome.icon.global_menu.mac", true);

// -- User Content -------------------------------------------------------------
// user_pref("userContent.player.ui.twoline", true);

// user_pref("userContent.newTab.hidden_logo", true);
// user_pref("userContent.newTab.background_image", true); // Need wallpaper image to `userContent.css`. :root { --uc-newTab-wallpaper: url("../icons/background_image.png"); }

// user_pref("userContent.page.proton_color.dark_blue_accent", true);
// user_pref("userContent.page.proton_color.system_accent", true);
// user_pref("userContent.page.dark_mode.pdf", true);
// user_pref("userContent.page.monospace", true);

// == Theme Default Settings ===================================================
// -- User Chrome --------------------------------------------------------------
user_pref("userChrome.compatibility.theme", true);
user_pref("userChrome.compatibility.os", true);

user_pref("userChrome.theme.built_in_contrast", true);
user_pref("userChrome.theme.system_default", true);
user_pref("userChrome.theme.proton_color", true);
user_pref("userChrome.theme.proton_chrome", true); // Need proton_color
user_pref("userChrome.theme.fully_color", true); // Need proton_color
user_pref("userChrome.theme.fully_dark", true); // Need proton_color

user_pref("userChrome.decoration.cursor", true);
user_pref("userChrome.decoration.field_border", true);
user_pref("userChrome.decoration.download_panel", true);
user_pref("userChrome.decoration.animate", true);

user_pref("userChrome.padding.tabbar_width", true);
user_pref("userChrome.padding.tabbar_height", true);
user_pref("userChrome.padding.toolbar_button", true);
user_pref("userChrome.padding.navbar_width", true);
user_pref("userChrome.padding.urlbar", true);
user_pref("userChrome.padding.bookmarkbar", true);
user_pref("userChrome.padding.infobar", true);
user_pref("userChrome.padding.menu", true);
user_pref("userChrome.padding.bookmark_menu", true);
user_pref("userChrome.padding.global_menubar", true);
user_pref("userChrome.padding.panel", true);
user_pref("userChrome.padding.popup_panel", true);

user_pref("userChrome.tab.multi_selected", true);
user_pref("userChrome.tab.unloaded", true);
user_pref("userChrome.tab.letters_cleary", true);
user_pref("userChrome.tab.close_button_at_hover", true);
user_pref("userChrome.tab.sound_hide_label", true);
user_pref("userChrome.tab.sound_with_favicons", true);
user_pref("userChrome.tab.pip", true);
user_pref("userChrome.tab.container", true);
user_pref("userChrome.tab.crashed", true);

user_pref("userChrome.fullscreen.overlap", true);
user_pref("userChrome.fullscreen.show_bookmarkbar", true);

user_pref("userChrome.icon.library", true);
user_pref("userChrome.icon.panel", true);
user_pref("userChrome.icon.menu", true);
user_pref("userChrome.icon.context_menu", true);
user_pref("userChrome.icon.global_menu", true);
user_pref("userChrome.icon.global_menubar", true);
user_pref("userChrome.icon.1-25px_stroke", true);

// -- User Content -------------------------------------------------------------
user_pref("userContent.player.ui", true);
user_pref("userContent.player.icon", true);
user_pref("userContent.player.noaudio", true);
user_pref("userContent.player.size", true);
user_pref("userContent.player.click_to_play", true);
user_pref("userContent.player.animate", true);

user_pref("userContent.newTab.full_icon", true);
user_pref("userContent.newTab.animate", true);
user_pref("userContent.newTab.pocket_to_last", true);
user_pref("userContent.newTab.searchbar", true);

user_pref("userContent.page.field_border", true);
user_pref("userContent.page.illustration", true);
user_pref("userContent.page.proton_color", true);
user_pref("userContent.page.dark_mode", true); // Need proton_color
user_pref("userContent.page.proton", true); // Need proton_color

// ** Useful Options ***********************************************************
// Tab preview
// https://blog.nightly.mozilla.org/2024/02/06/a-preview-of-tab-previews-these-weeks-in-firefox-issue-153/
user_pref("browser.tabs.cardPreview.enabled", true);

// Paste suggestion at urlbar
// https://blog.nightly.mozilla.org/2023/12/04/url-gonna-want-to-check-this-out-these-weeks-in-firefox-issue-150/
user_pref("browser.urlbar.clipboard.featureGate", true);

// Integrated calculator at urlbar
user_pref("browser.urlbar.suggest.calculator", true);

// Integrated unit convertor at urlbar
// user_pref("browser.urlbar.unitConversion.enabled", true);

// Draw in Titlebar
// user_pref("browser.tabs.drawInTitlebar", true);
// user_pref("browser.tabs.inTitlebar", 1); // Nightly, 96 Above

// Searchbar, Removed from settings starting with FF v122
// user_pref("browser.search.widget.inNavBar", true);

// Firefox view search
// https://blog.nightly.mozilla.org/2023/12/14/better-searching-in-firefox-to-close-out-2023-these-weeks-in-firefox-issue-151/
// user_pref("browser.firefox-view.search.enabled", true);
// user_pref("browser.firefox-view.virtual-list.enabled", true);

// Firefox screenshot
// https://blog.nightly.mozilla.org/2024/01/22/happy-new-year-these-weeks-in-firefox-issue-152/
// user_pref("screenshots.browser.component.enabled", true);

// ** Scrolling Settings *******************************************************
// == Only Sharpen Scrolling ===================================================
// Pref Value Original
/*
user_pref("mousewheel.min_line_scroll_amount", 10); // 5
user_pref("general.smoothScroll.mouseWheel.durationMinMS", 80); // 50
user_pref("general.smoothScroll.currentVelocityWeighting", "0.15"); // "0.25"
user_pref("general.smoothScroll.stopDecelerationWeighting", "0.6"); // "0.4"
*/

// == Smooth Scrolling ==========================================================
// ** Scrolling Options ********************************************************
// based on natural smooth scrolling v2 by aveyo
// this preset will reset couple extra variables for consistency
// Pref Value Original
/*
user_pref("apz.allow_zooming", true); /// true
user_pref("apz.force_disable_desktop_zooming_scrollbars", false); /// false
user_pref("apz.paint_skipping.enabled", true); /// true
user_pref("apz.windows.use_direct_manipulation", true); /// true
user_pref("dom.event.wheel-deltaMode-lines.always-disabled", true); /// false
user_pref("general.smoothScroll.currentVelocityWeighting", "0.12"); /// "0.25" <- 1. If scroll too slow, set to "0.15"
user_pref("general.smoothScroll.durationToIntervalRatio", 1000); /// 200
user_pref("general.smoothScroll.lines.durationMaxMS", 100); /// 150
user_pref("general.smoothScroll.lines.durationMinMS", 0); /// 150
user_pref("general.smoothScroll.mouseWheel.durationMaxMS", 100); /// 200
user_pref("general.smoothScroll.mouseWheel.durationMinMS", 0); /// 50
user_pref("general.smoothScroll.mouseWheel.migrationPercent", 100); /// 100
user_pref("general.smoothScroll.msdPhysics.continuousMotionMaxDeltaMS", 12); /// 120
user_pref("general.smoothScroll.msdPhysics.enabled", true); /// false
user_pref("general.smoothScroll.msdPhysics.motionBeginSpringConstant", 200); /// 1250
user_pref("general.smoothScroll.msdPhysics.regularSpringConstant", 200); /// 1000
user_pref("general.smoothScroll.msdPhysics.slowdownMinDeltaMS", 10); /// 12
user_pref("general.smoothScroll.msdPhysics.slowdownMinDeltaRatio", "1.20"); /// "1.3"
user_pref("general.smoothScroll.msdPhysics.slowdownSpringConstant", 1000); /// 2000
user_pref("general.smoothScroll.other.durationMaxMS", 100); /// 150
user_pref("general.smoothScroll.other.durationMinMS", 0); /// 150
user_pref("general.smoothScroll.pages.durationMaxMS", 100); /// 150
user_pref("general.smoothScroll.pages.durationMinMS", 0); /// 150
user_pref("general.smoothScroll.pixels.durationMaxMS", 100); /// 150
user_pref("general.smoothScroll.pixels.durationMinMS", 0); /// 150
user_pref("general.smoothScroll.scrollbars.durationMaxMS", 100); /// 150
user_pref("general.smoothScroll.scrollbars.durationMinMS", 0); /// 150
user_pref("general.smoothScroll.stopDecelerationWeighting", "0.6"); /// "0.4"
user_pref("layers.async-pan-zoom.enabled", true); /// true
user_pref("layout.css.scroll-behavior.spring-constant", "250.0"); /// "250.0"
user_pref("mousewheel.acceleration.factor", 3); /// 10
user_pref("mousewheel.acceleration.start", -1); /// -1
user_pref("mousewheel.default.delta_multiplier_x", 100); /// 100
user_pref("mousewheel.default.delta_multiplier_y", 100); /// 100
user_pref("mousewheel.default.delta_multiplier_z", 100); /// 100
user_pref("mousewheel.min_line_scroll_amount", 0); /// 5
user_pref("mousewheel.system_scroll_override.enabled", true); /// true <- 2. If scroll too fast, set to false
user_pref("mousewheel.system_scroll_override_on_root_content.enabled", false); /// true
user_pref("mousewheel.transaction.timeout", 1500); /// 1500
user_pref("toolkit.scrollbox.horizontalScrollDistance", 4); /// 5
user_pref("toolkit.scrollbox.verticalScrollDistance", 3); /// 3
*/
```

### Additional context

_No response_

Start by reproducing the reported corners and checkbox behavior in Firefox v127 on Windows 10, with the listed userChrome.rounding.square_checklabel preference enabled in about:config. Work through the affected areas in the issue, beginning with the reader panel and menus, and define completion as consistent square corners and working square checkboxes across the confirmed cases.

Written by the indexing model from the issue text.