The OP asked if something was done to the fuse because it does sound different.
You’ve been told, it’s not the fuse, but the way it’s seated in the fuse holder that gives a very small voltage drop across the fuse (unlikely detectable)
To the OP adam8179
If it worries you just do a clean, up and push the fuse clamper together a bit to give it better holding tension. And use a new 10c fuse if it looks like these
Also the standard fuse could have had many turn on cycles, and become crusty, hardened and carbonized.And don’t be gullible and spend $160 on 10c re-badged fuses
Left to right aging same fuse https://ibb.co/SQ9WJLn
Right to left aging same fuse https://ibb.co/S6YXQGT
Cheers George