Decepticon
Senior Member
Các thym thấy Firefox của mình đã đẹp nhất chưa 
userChrome.css của mềnh
P/s: muốn tab ngăn chứa luôn hiện vạch màu cần sửa css ntn thym @Fioren nhỉ? click vào mới hiện bất tiện quá >"<

userChrome.css của mềnh

CSS:
/*** Tighten up drop-down/context/popup menu spacing (8 Sep 2021) ***/
menupopup:not(.in-menulist) > menuitem,
menupopup:not(.in-menulist) > menu {
padding-block: 4px !important; /* reduce to 3px, 2px, 1px or 0px as needed */
min-height: unset !important; /* v92.0 - for padding below 4px */
}
:root {
--arrowpanel-menuitem-padding: 4px 8px !important;
}
/*** Photon-like Menu Colors (14 Jan 2022) ***/
/* Bookmarks Toolbar folders */
#PersonalToolbar menupopup,
/* Right-click context menus */
#mainPopupSet menupopup,
/* Top menu bar on Windows (not sure about others) */
#toolbar-menubar menupopup,
/* Sidebar/Library bookmark/history context menus */
#placesContext,
/* Address bar context menu (2021-10-25) */
#urlbar-input-container menupopup,
/* Various toolbar drop-down panels (Fx96) */
#back-button menupopup, #forward-button menupopup,
#identity-popup, #appMenu-popup, #downloadsPanel, #BMB_bookmarksPopup {
/* Text color */
--menu-color: #000 !important;
--arrowpanel-color: #000 !important;
--panel-color: #000 !important;
/* Background color */
--menu-background-color: #f0f0f0 !important;
--arrowpanel-background: #f0f0f0 !important;
--panel-background: #f0f0f0 !important;
/* Border color (if any) */
--menu-border-color: threedshadow !important;
--arrowpanel-border-color: threedshadow !important;
--panel-border-color: threedshadow !important;
/* Hovered/expanded item background color */
--menuitem-hover-background-color: #e0e0e6 !important;
--button-hover-bgcolor: #e0e0e6 !important;
/* Disabled items text color and hovered background */
--menu-disabled-color: rgba(21, 20, 26, 0.4) !important;
--menuitem-disabled-hover-background-color: rgba(224, 224, 230, 0.4) !important;
}
/* TAB BAR ------------------------------------------------------------------------------------------------- */
/* sets the height of the tab toolbar
otherwise will change height when tabs overflow [FIXED] */
/* tab height when playing audio issue fixed in FF 96.0.2+ */
/* https://bugzilla.mozilla.org/show_bug.cgi?id=1714276 */
/* height change when tab overflow fixed in FF 97 beta+ */
/* Reduce left spacer on tab bar */
.titlebar-spacer[type="pre-tabs"] {
display: none !important;
}
/* Tab - Connect to window */
.tab-background {
border-radius: 0 !important;
margin-top: 0 !important;
margin-bottom: 0 !important;
}
.tab-content {
margin-top: 0 !important;
margin-bottom: 0 !important;
}
.tab-stack {
margin-top: 0 !important;
margin-bottom: 0 !important;
}
/* make context line (from container tabs) visible */
.tabbrowser-tab[selected] .tab-context-line {
margin-top: 0 !important;
margin-left: 0 !important;
margin-right: 0 !important;
border-radius: 0 !important;
}
/* realign the selected tab so it doesnt droop down by 2px */
.tabbrowser-tab[visuallyselected="true"]{
z-index: 0 !important;
}
/* neighbouring tabs should "pinch" together */
.tabbrowser-tab {padding-inline: 0 !important;}
/* Unselected Tab - Divide line */
.tab-content::before,
.tab-content::after {
content: "" !important;
display: block !important;
position: absolute !important;
background-color: var(--custom-tab-divider-color, #535354) !important;
width: 1px !important;
height: 40px !important;
transform: translateY(-20px) !important;
opacity: 0 !important;
transition: opacity 1s var(--ease-basic) !important;
}
.tab-content::before {left: 0 !important;}
.tab-content::after {right: 0 !important;}
.tabbrowser-tab[visuallyselected][style*=transform] + .tabbrowser-tab[style*=transform] .tab-content::after,
.tabbrowser-tab[style*=transform]:not([visuallyselected]) .tab-content::before,
.tabbrowser-tab[style*=transform] + .tabbrowser-tab:not([visuallyselected]) .tab-content::before,
.tabbrowser-tab:not([visuallyselected]):not(:hover):not([multiselected]) + .tabbrowser-tab:not([visuallyselected]):not(:hover):not([multiselected]) .tab-content::before,
#tabbrowser-tabs[hasadjacentnewtabbutton]:not([overflow]) .tabbrowser-tab[last-visible-tab]:not([visuallyselected]):not(:hover):not([multiselected]) .tab-content::after {
opacity: var(--tab-separator-opacity) !important;
}
/* squares the mute button on hover */
.tab-icon-overlay:not([pinned], [sharing], [crashed]):is([soundplaying], [muted], [activemedia-blocked]) {
border-radius: 0 !important;
}
P/s: muốn tab ngăn chứa luôn hiện vạch màu cần sửa css ntn thym @Fioren nhỉ? click vào mới hiện bất tiện quá >"<


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