Hi Marwin!
I guess you mean
DownThemAll! (a download manager for Firefox) and
DownloadHelper (addon for downloading videos from various sites like Youtube, for example).
To install these, do the following:
1. From the pulldown-menu at the top called "Extras", choose "Add-ons".
2. In the Add-on window, there's a link at the buttom right corner labelled "Download extensions" (or "Erweiterungen herunterladen" in German). Click this link to get to the official add-on download page from Mozilla Firefox (you should never download Add-ons from elsewhere, because they might contain malicious code).
3. Enter the name of the desired add-on into the search field on top of the page. Once you found it, simply click "Add to Firefox" (or "Zu Firefox hinzufügen" in German). That's all.
4. After Firefox has restarted, you should configure the newly installed add-ons. To do so, you must open the add-ons window again (see 1.), select the add-on in the list and choose "Configure" (or "Einstellungen" in German).
The attached snapshot at the end of my post shows the add-ons window and the link to click to download add-ons. By the way: You can install themes (to change the look of Firefox) in the same manner. Simply click the tab "Themes" on top of the add-ons window to do so.
I would recommend the following add-ons:
-
NoScript (allows you to easily enable Javascript, Java, Flash, etc. for any specific website [temporarily, which means until you close the browser, or fixed, which means that Firefox will save this setting])
-
CookieSafe (does the same as NoScript for Cookies - you can also allow them just for a session, which means that Firefox will remember your setting, but the cookies for this site will be deleted every time you close the browser)
-
Adblock Plus (eliminates advertisements from webpages - just check the
Heise newsticker to test this!)
-
Update Notifier (checks for Updates of any installed add-ons every time the browser is started)
-
DownloadHelper (to save videos from websites)
-
DownThemAll! (powerful download manager - spilts downloads into multiple segments for faster downloading from slow pages, auto-resumes aborted transfers, lets you create a list of files to download which are transferred in a row without the need to pay any further attention)
Browsing the add-ons download page, you will find lots more of useful add-ons.
The theme I use for Firefox is called
Fusion Alternative 2 by the way, just in case you want to give it a try.
Coco.