Stable AMO Version, see changelog for details.
You can get latest stable version here, too, using this
direct download link for FlashGot
To install, just drag and drop it onto your address bar.
If you find any problem installing it, this FAQ may help.
If you're brave enough and you need a specific fix not released yet, or you simply
want to provide feedback before official release, you may try this
v 18.104.22.168rc2 ===================================================== x [Media] Fixed Youtube multiple formats sniffing sometimes causing detected streams to be prefetched x [Media] Restored compatibility with Gecko < 2.0 x [Built-in DM] User-facing error message if the directory selected for download doesn't exist and cannot be created v 22.214.171.124rc1 ===================================================== x [Built-in DM] User-facing error message if the downloaded file cannot be written on disk
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