enchant effect outlines full inventory tile

Can confirm.
Although not sure weather feature or bug.

Glitter effect of enchanted items covers the whole inventory slot in the hotbar - not so if you open the inventory. Also the glitter effect around the item is a square in the player preview.

EDIT: Glitter effect filling the whole inventory slot is barely visible in screenshot. See second screenshot.

Odd, I cannot reproduce.

I can confirm this.

Unable to reproduce. For those of you experiencing this, please force a crash by pressing F3 + C for 10 seconds while in-game and put the crash report ([minecraft|http://hopper.minecraft.net/help/finding-minecraft-data-folder]/crash-reports/crash-<DATE>-client.txt) in a comment here.

I am as well not able any more to reproduce, although it "worked" yesterday. Conditions stayed the same, same environment, same minecraft world, same settings.
Also the player character is now shown correctly in the inventory preview, which was not the case before, as is obvious from the screenshot.

Once again a EDIT: Switching graphics to "Fast" reproduces the glitter effect being over the whole inventory tile. However I am still unable to reproduce the glitter effect being a square in the player preview as well. Player preview looks fine in other regards as well, so maybe this portion of the bug is more related to the reported bugs of rendering glitches in the player preview. (Why those vanished "over night" is still strange, though.)
The enchanted item may not have the enchantment effect over the whole tile instantly. In my case I first had to rearrange it a couple of times in the hotbar.

Sure it's not better to add as a text file?

---- Minecraft Crash Report ----
// Why did you do that?

Time: 30/07/15 09:25
Description: Manually triggered debug crash

java.lang.Throwable
	at axc.s(SourceFile:1566)
	at axc.at(SourceFile:874)
	at axc.a(SourceFile:323)
	at net.minecraft.client.main.Main.main(SourceFile:125)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
	at bfb.a(SourceFile:309)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bgz['_DeltaForce_'/5564, l='MpServer', x=-372.60, y=69.00, z=227.87]]
	Chunk stats: MultiplayerChunkCache: 412, 412
	Level seed: 0
	Level generator: ID 00 - default, ver 1. Features enabled: false
	Level generator options: 
	Level spawn location: -240.00,64.00,244.00 - World: (-240,64,244), Chunk: (at 0,4,4 in -15,15; contains blocks -240,0,240 to -225,255,255), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
	Level time: 123925 game time, 1000 day time
	Level dimension: 0
	Level storage version: 0x00000 - Unknown?
	Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
	Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
	Forced entities: 81 total; [wa['Creeper'/13347, l='MpServer', x=-329.50, y=51.00, z=288.50], wa['Creeper'/45909, l='MpServer', x=-304.50, y=44.00, z=161.50], tx['Chicken'/13826, l='MpServer', x=-431.50, y=44.00, z=187.50], wr['Zombie'/10441, l='MpServer', x=-435.50, y=34.00, z=275.50], ui['Squid'/64364, l='MpServer', x=-424.53, y=61.00, z=272.88], ui['Squid'/64363, l='MpServer', x=-425.50, y=60.91, z=280.50], wa['Creeper'/8563, l='MpServer', x=-357.50, y=42.00, z=220.91], ui['Squid'/64362, l='MpServer', x=-423.78, y=61.00, z=276.56], wa['Creeper'/8562, l='MpServer', x=-358.94, y=36.00, z=226.56], ui['Squid'/64361, l='MpServer', x=-424.16, y=61.97, z=273.19], tu['Bat'/59519, l='MpServer', x=-360.53, y=46.31, z=217.19], tu['Bat'/59518, l='MpServer', x=-354.59, y=39.72, z=194.50], tu['Bat'/52351, l='MpServer', x=-307.50, y=17.10, z=170.25], wr['Zombie'/63562, l='MpServer', x=-316.50, y=18.00, z=176.50], tu['Bat'/64517, l='MpServer', x=-319.41, y=55.01, z=172.43], tu['Bat'/64516, l='MpServer', x=-302.15, y=51.11, z=165.52], wr['Zombie'/63836, l='MpServer', x=-321.50, y=21.00, z=151.50], wn['Skeleton'/14538, l='MpServer', x=-312.50, y=17.00, z=174.50], ty['Cow'/5446, l='MpServer', x=-298.84, y=68.00, z=229.09], tz['Horse'/5445, l='MpServer', x=-305.91, y=70.00, z=196.75], ty['Cow'/5444, l='MpServer', x=-297.72, y=70.00, z=194.25], ty['Cow'/5443, l='MpServer', x=-299.22, y=71.00, z=181.22], wa['Creeper'/63558, l='MpServer', x=-426.50, y=36.00, z=185.50], wa['Creeper'/64867, l='MpServer', x=-330.50, y=27.00, z=153.50], wa['Creeper'/64866, l='MpServer', x=-327.83, y=27.00, z=155.69], tu['Bat'/63788, l='MpServer', x=-352.84, y=36.97, z=241.44], wr['Zombie'/64871, l='MpServer', x=-331.50, y=27.00, z=153.50], wa['Creeper'/64868, l='MpServer', x=-328.72, y=27.00, z=156.01], tu['Bat'/63784, l='MpServer', x=-430.09, y=43.16, z=186.28], ty['Cow'/5424, l='MpServer', x=-308.19, y=71.00, z=183.84], ty['Cow'/5425, l='MpServer', x=-303.03, y=70.00, z=196.06], ty['Cow'/5426, l='MpServer', x=-307.75, y=69.00, z=217.41], wv['Villager'/5427, l='MpServer', x=-309.69, y=68.00, z=243.16], ty['Cow'/5428, l='MpServer', x=-309.47, y=65.00, z=261.47], ty['Cow'/5429, l='MpServer', x=-310.56, y=64.00, z=280.53], ty['Cow'/5419, l='MpServer', x=-307.72, y=70.00, z=164.72], ty['Cow'/5418, l='MpServer', x=-313.75, y=70.00, z=159.16], ty['Cow'/5423, l='MpServer', x=-308.97, y=71.00, z=188.09], ty['Cow'/5422, l='MpServer', x=-311.00, y=71.00, z=186.88], ty['Cow'/5411, l='MpServer', x=-314.06, y=70.00, z=154.03], ty['Cow'/5410, l='MpServer', x=-305.97, y=71.00, z=151.91], wa['Creeper'/65150, l='MpServer', x=-355.50, y=34.00, z=235.50], wa['Creeper'/65151, l='MpServer', x=-357.50, y=34.00, z=235.50], wn['Skeleton'/64583, l='MpServer', x=-325.50, y=50.00, z=294.50], wp['Spider'/64580, l='MpServer', x=-323.50, y=50.00, z=293.50], ty['Cow'/5383, l='MpServer', x=-404.69, y=68.00, z=244.78], ty['Cow'/5382, l='MpServer', x=-347.19, y=71.00, z=163.75], px['Experience Orb'/14181, l='MpServer', x=-344.25, y=68.00, z=222.72], ty['Cow'/5351, l='MpServer', x=-390.81, y=71.00, z=212.91], ty['Cow'/5348, l='MpServer', x=-387.25, y=63.00, z=265.56], ty['Cow'/5346, l='MpServer', x=-395.69, y=64.00, z=192.16], ty['Cow'/5347, l='MpServer', x=-399.69, y=68.00, z=254.78], ty['Cow'/5344, l='MpServer', x=-401.44, y=64.00, z=189.72], ty['Cow'/5345, l='MpServer', x=-389.38, y=63.00, z=189.22], ty['Cow'/5356, l='MpServer', x=-409.88, y=70.00, z=237.97], ty['Cow'/5357, l='MpServer', x=-372.25, y=64.00, z=269.16], tu['Bat'/64216, l='MpServer', x=-326.41, y=52.94, z=290.41], ty['Cow'/5353, l='MpServer', x=-378.78, y=63.00, z=268.25], ty['Cow'/5366, l='MpServer', x=-354.72, y=70.00, z=164.34], ty['Cow'/5365, l='MpServer', x=-352.63, y=69.00, z=162.19], ty['Cow'/5364, l='MpServer', x=-362.78, y=71.00, z=170.69], wa['Creeper'/65152, l='MpServer', x=-358.50, y=34.00, z=232.50], wr['Zombie'/37049, l='MpServer', x=-408.50, y=16.00, z=176.50], ty['Cow'/5370, l='MpServer', x=-364.03, y=69.00, z=251.91], ty['Cow'/5368, l='MpServer', x=-381.51, y=69.00, z=224.08], ui['Squid'/40260, l='MpServer', x=-375.16, y=61.03, z=278.09], vm['item.item.beefRaw'/13997, l='MpServer', x=-348.47, y=68.00, z=221.97], vm['item.item.leather'/13995, l='MpServer', x=-348.03, y=68.00, z=222.59], wn['Skeleton'/63961, l='MpServer', x=-362.47, y=28.00, z=284.91], wn['Skeleton'/63962, l='MpServer', x=-355.50, y=27.00, z=293.50], bgz['_DeltaForce_'/5564, l='MpServer', x=-372.60, y=69.00, z=227.87], tu['Bat'/65002, l='MpServer', x=-422.75, y=45.09, z=251.75], wa['Creeper'/38060, l='MpServer', x=-300.50, y=48.00, z=157.50], wr['Zombie'/38061, l='MpServer', x=-342.66, y=54.00, z=284.34], tu['Bat'/59521, l='MpServer', x=-325.13, y=27.00, z=162.47], wr['Zombie'/57275, l='MpServer', x=-450.50, y=45.00, z=179.50], wa['Creeper'/64168, l='MpServer', x=-310.69, y=17.00, z=175.66], wr['Zombie'/64169, l='MpServer', x=-311.34, y=17.00, z=167.81], wa['Creeper'/64173, l='MpServer', x=-337.50, y=29.00, z=188.50], wa['Creeper'/64174, l='MpServer', x=-337.50, y=29.00, z=189.50], wr['Zombie'/64175, l='MpServer', x=-337.50, y=29.00, z=190.50]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at bfb.a(SourceFile:309)
	at axc.b(SourceFile:2293)
	at axc.a(SourceFile:332)
	at net.minecraft.client.main.Main.main(SourceFile:125)

-- System Details --
Details:
	Minecraft Version: 15w31a
	Operating System: Linux (amd64) version 3.13.0-37-generic
	Java Version: 1.7.0_79, Oracle Corporation
	Java VM Version: OpenJDK 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 183655160 bytes (175 MB) / 396726272 bytes (378 MB) up to 1060372480 bytes (1011 MB)
	JVM Flags: 5 total; -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
	IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
	Launched Version: 15w31a
	LWJGL: 2.9.4
	OpenGL: GeForce 8600M GT/PCIe/SSE2 GL version 3.3.0 NVIDIA 331.113, NVIDIA Corporation
	GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Shaders are available because OpenGL 2.1 is supported.
VBOs are available because OpenGL 1.5 is supported.

	Using VBOs: No
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Packs: 
	Current Language: English (US)
	Profiler Position: N/A (disabled)
	CPU: 2x Intel(R) Core(TM)2 Duo CPU T8100 @ 2.10GHz

fixed in 15w31b for me

Still present in 15w31b.

@FVbico: Did you switch the graphics settings to "Fast"?

Not sure about 15w31b but it's not happening to me in 15w31c