I put some signs in the world. And I use cmdblocks to edit it's content with scoreboard objectives. But after killing myself and respawning, other signs in the same chunk will disappear. F3+A and F3+T can not solve the problem. But I can still "point" the "hidden" signs. If I break a "hidden" sign in survival mode, the sign will be displayed but the content on the sign is still invisible. Leave and reenter the world can solve it. The issues happens both when opened Optifine and when not.

How to reproduce

1. Create a dummy scoreboard objective (for example, "f"). (You can use an obj that I have already used.)
2. Place a sign (both wall sign and standing sign are ok).
3. Place a repeating command block, and make it always work without restone.
4. Edit the cmdblock's cmd. It should change the sign's data and the content should include the scoreboard. For example,

   /blockdata <position of the sign you placed> {Text1:"{\"score\":{\"name\":\"@p\",\"objective\":\"star1\"}}"}

5. Set your respawn point here.
6. Put other signs in the same chunk. (You can use F3+G.)
7. /kill and respawn.
8. You will find that other signs are hidden. But signs out of this chunk are normal.

(I'm bad at English, so I provide the Chinese content.)

如何重现

1. 创建一个记分板项目（例如“f”）。（你可以使用一个已存在的记分板项目。）
2. 放置一个告示牌（墙上或站立均可）。
3. 放置循环型命令方块，并且设为“总是执行”。
4. 编辑命令，使其修改那个告示牌的内容。内容需要包括记分板项目。例如，

   /blockdata <position of the sign you placed> {Text1:"{\"score\":{\"name\":\"@p\",\"objective\":\"star1\"}}"}

5. 在原地设置重生点
6. 在同一个区块内再放几个告示牌。
7. /kill，然后重生。
8. 你会发现区块内的告示牌都消失了，而区块外的告示牌安然无恙。