You can switch windows without minimizing by using Borderless windowed mode.
This can be done in a couple ways, the easiest is by going into your "Options> Video" settings in game and setting the game to "Run in a Window".
Alternatively you can modify your launch settings by adding the launch options -windowed -noborder in the TF2s "Properties > General" ...
I believe the setting you're looking for is borderless windowed mode in team fortress 2. As the name suggests, it puts the game in windowed mode but removes the border, so it should still appear as full screen. That should fix your issue and allow you to click without minimizing!
You can only get to drop half (rounded up) of the cards for a game. If a game has 7 or 8 cards you can only drop 4, if it has 9 or 10 then only 5, etc.
As for TF2, if you click "How do I earn card drops?" on your Team Fortress 2 Badge page, you would see the explanation:
How can I earn more drops?
You can receive additional card drops as a reward ...
Yep, you've got it. When a medic gets an assist while using a medigun, that assist will be be counted as a kill for the purposes of the killstreak counter. Mediguns work exactly the same as normal killstreak weapons which gain effects upon hitting kill threshholds, except that the counter is increased by getting assists.
Here's a video showing the medic ...
This isn't a glitch, it is by design.
The number of cards varies for each game but you can usually on earn 3 or 4 cards by playing, after that you have to either trade for them, buy them in the marketplace or be lucky enough to earn a random booster pack.
If you look at the 'badges' page under the tab with your profile name, your progress and how many ...
Valve says they updated the achievements. This is from the Jungle Inferno patch notes.
Long-range ball impacts no longer remove the victim's ability to fire their weapon (but the victim is still slowed)
We've updated achievements that were looking for disarmed players.
People on reddit confirm it is still possible to get the Moon Shot achievement, ...
As of June 7 2018, you can reset achievements in Team Fortress 2 from the "View Achievements" menu.
Added "Reset All Achievements" button to the Achievements dialog
A small number of achievements are based on player stats and will be awarded again when Team Fortress 2 is restarted unless the player stats are also reset
Resetting achievements ...
I addition to the in-game option mentioned in the main answer, you can use Steam Launch options - I use these for Counter Strike and they work for TF2 as well.
-window -noborder -novid -nojoy -w 2560 -h 1080
No once you have got the achievement item you can't get it again. Steam support aren't going to give you another one. Crafting with Achievement items makes the items untradable aswell so its a pretty bad idea to smelt the weapons down to scrap.