Alles paletti.... Habe jetzt deinen Code dem bestehenden hinzugefügt und Firefox einmal neu gestartet...
[attachment=0]2012-10-24_170807.jpg[/attachment]
Vielen Dank.... 
Jetzt kann ich wieder beruhigt schlafen... :mrgreen:
Hier nochmal der jetzt gut funktionierende komplette Code:
CSS
@-moz-document url("about:addons"),
url("chrome://mozapps/content/extensions/extensions.xul") {
#categories {
min-width: 0 !important;
}
/*/*[[categorylabel]]*/
.category > .category-name {
display: none !important;
}/**/
/*/*[[globalwarning]]*/
.global-warning-container {
display: none !important;
}/**/
.addon {
-moz-box-direction: reverse !important;
}
/*/*[[addonwarning]]*/
.addon > .warning {
display: none !important;
}/**/
.addon > :-moz-any(.warning, .error, .pending) > image {
margin: 0 -6px 0 0.2em !important;
list-style-image: none !important;
}
.addon .icon-container {
width: 16px !important;
height: 16px !important;
margin-right: 0.7em !important;
padding: 0 !important;
}
.addon .icon {
width: 16px !important;
height: 16px !important;
}
.addon :-moz-any(.name-container, .name) {
font-size: inherit !important;
}
.addon:not([selected]) .content-inner-container {
-moz-box-orient: horizontal !important;
}
.addon:not([selected]) .basicinfo-container {
-moz-box-flex: 1000 !important;
}
.addon:not([selected]) .advancedinfo-container {
margin-left: 1em !important;
-moz-box-align: center !important;
}
.addon:not([selected]) :-moz-any(.control-container, .details) {
display: none !important;
}
.addon-control {
-moz-transition: none !important;
}
}
@-moz-document url("about:addons") {
#view-port-container {
border-radius: 0px !important;
}
/*******PUTs EVERYTHING AS ONE LINE******/
#list-view > #addon-list .addon.addon-view {
padding: 2px 12px 2px 7px !important;
}
#list-view .addon.addon-view * {
-moz-box-orient: horizontal !important;
-moz-box-align: center !important;
vertical-align: middle !important;
font-size: 100% !important;
margin-top: 0 !important;
margin-bottom: 0 !important;
margin-right: 0 !important;
white-space: nowrap !important;
}
#list-view > #addon-list .icon-container,
#list-view > #addon-list .icon {
height: 16px !important;
width: 16px !important;
}
#list-view > #addon-list :-moz-any(
.icon-container,
.name,
.version,
.disabled-postfix,
.update-postfix,
.date-updated,
.description,
.details.buttton-link,
.relnotes-toggle),
#list-view > #addon-list .relnotes-container > *,
#list-view > #addon-list .status-container label {
margin-left: 5px !important;
}
#list-view > #addon-list .name-container {
padding-top: 1px !important;
padding-bottom: 2px !important;
}
#list-view > #addon-list .date-updated {
display: -moz-box !important;
}
#list-view > #addon-list .description-container,
#list-view > #addon-list .relnotes-container {
margin: 0 !important;
}
#list-view > #addon-list .description {
padding-top: 1px !important;
padding-bottom: 2px !important;
}
#list-view > #addon-list .details.button-link > hbox {
padding-left: 0 !important;
padding-right: 0 !important;
}
/******COLUMNS ADJUSTMENT******/
#list-view > #addon-list > .addon.addon-view {
min-width: -moz-calc(21em + 3em + 19px) !important;
}
#list-view > #addon-list .content-container {
min-width: -moz-calc(21em + 3em + 19px) !important;
}
#list-view > #addon-list .content-inner-container {
/* max-width: -moz-calc(100% - 12px - 12px - 16px - 7px - 7px) !important;
width: -moz-calc(100% - 12px - 12px - 16px - 7px - 7px) !important; */
max-width: 100% !important;
width: 100% !important;
min-width: -moz-calc(21em + 3em + 5px) !important;
display: inline-table !important;
}
/***BASICINFO-CONTAINER***/
#list-view > #addon-list .basicinfo-container {
width: 55% !important;
max-width: -moz-calc(100% - 21em - 3em - 5px - 7px) !important;
min-width: 0 !important;
display: inline-table !important;
}
#list-view > #addon-list .name-container {
width: -moz-calc(66% - 5px) !important;
max-width: -moz-calc(66% - 5px) !important;
min-width: 0 !important;
display: inline-table !important;
}
/*****enabled addon*****/
#list-view > #addon-list > .addon.addon-view[active="true"]:not([upgrade="true"]) .name {
max-width: -moz-calc(65% - 5px) !important;
min-width: 0 !important;
}
#list-view > #addon-list > .addon.addon-view[active="true"]:not([upgrade="true"]) .version {
max-width: -moz-calc(35%) !important;
width: -moz-calc(35%) !important;
min-width: 0 !important;
}
#list-view > #addon-list .version[hidden],
#list-view > #addon-list > .addon.addon-view[active="true"] .disabled-postfix,
#list-view > #addon-list > .addon.addon-view:not([upgrade="true"]) .update-postfix {
width: 0 !important;
max-width: 0 !important;
}
/***disabled addon***/
#list-view > #addon-list > .addon.addon-view[active="false"] .name,
#list-view > #addon-list > .addon.addon-view[upgrade="true"] .name {
max-width: -moz-calc(55% - 5px) !important;
min-width: 0 !important;
}
#list-view > #addon-list > .addon.addon-view[active="false"] .version,
#list-view > #addon-list > .addon.addon-view[upgrade="true"] .version {
max-width: -moz-calc(27% - 5px) !important;
min-width: 0 !important;
}
#list-view > #addon-list > .addon.addon-view[active="false"] .disabled-postfix {
max-width: 18% !important;
width: 18% !important;
min-width: 0 !important;
}
#list-view > #addon-list > .addon.addon-view[upgrade="true"] .update-postfix {
max-width: 18% !important;
width: 18% !important;
min-width: 0 !important;
}
#list-view > #addon-list .date-updated {
width: -moz-calc(34%) !important;
max-width: -moz-calc(34%) !important;
min-width: 0 !important;
}
/***DESCRIPTION AND BUTTONS***/
#list-view > #addon-list .advancedinfo-container {
width: 45% !important;
min-width: 21em !important;
display: inline-table !important;
}
/****** DESCRIPTION + MORE + RELNOTES ******/
#list-view > #addon-list .description-outer-container {
width: -moz-calc(100% - 21em - 5px) !important;
max-width: -moz-calc(100% - 21em - 5px) !important;
min-width: 4em !important;
display: inline-table !important;
}
#list-view > #addon-list .description-container {
width: 100% !important;
min-width: 100% !important;
display: inline-table !important;
}
#list-view > #addon-list .description {
width: -moz-calc(100% - 3em - 5px) !important;
max-width: -moz-calc(100% - 3em - 5px) !important;
display: table-cell !important;
}
#list-view > #addon-list .description[hidden] + .details.button-link {
margin-left: -moz-calc(-3em + 1px) !important;
}
#list-view > #addon-list .details.button-link {
max-width: 3em !important;
display: table-cell !important;
}
#list-view > #addon-list .relnotes-container {
}
/***BUTTONS***/
#list-view > #addon-list .status-control-wrapper {
width: 21em !important;
max-width: 21em !important;
min-width: 21em !important;
-moz-box-pack: end !important;
}
/***BUTTONS***/
#list-view > #addon-list .control-container > :-moz-any(.preferences, .enable, .disable, .remove) {
width: 6.4em !important;
min-width: 6.4em !important;
}
/******MESSAGES ADJUSTMENTS******/
#list-view > #addon-list :-moz-any(.error, .pending, .warning) {
margin-left: 28px !important;
}
#list-view .addon.addon-view[notification="warning"] .warning {
display: none !important;
}
/******UPDATE PROGRESS BAR******/
#list-view > #addon-list > .addon.addon-view .install-status:not([hidden]) .cancel {
margin: 3px !important;
}
#list-view > #addon-list > .addon.addon-view .install-status:not([hidden]) .start-cap {
margin: -1px 0 -1px -1px !important;
height: 1.7em !important;
}
}
#category-discover {
display: none;
}
@-moz-document url("about:addons"){
[oncommand="Services.wm.getMostRecentWindow('navigator:browser').document.defaultView.OpenAddonFolder.OpenFolder()"] {
-moz-binding:
url("chrome://global/content/bindings/menu.xml#menuitem-iconic") !important;
list-style-image: url("data:image/png;base64,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") !important;
-moz-image-region: rect(0px 16px 16px 0px) !important;
padding-left:4px!important}
menuitem[label="Addon-Ordner öffnen"] >.menu-iconic-text{
padding-left:10px !important;}
}
[oncommand="Services.wm.getMostRecentWindow('navigator:browser').document.defaultView.OpenAddonFolder.OpenFolder()"] >.menu-iconic-text{
padding-left:10px !important;}