Issue:
While a backpack is open, player is able to click through the screen to select menus in the background.

Steps to reproduce:

1. Open backpack
2. Click on the right side of the screen where REI is (which closes the backpack and brings up a recipe screen)
3. Press escape to close recipe screen
4. Game crashes

Proposed solution:
Disable the player from being able to click on things behind the backpack screen while the backpack is open. (escape key to close backpack)

`---- Minecraft Crash Report ----
// Hi. I'm Minecraft, and I'm a crashaholic.

Time: 7/29/20 10:41 AM
Description: keyPressed event handler

java.lang.ArrayIndexOutOfBoundsException

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

-- Head --
Thread: Render thread
Stacktrace:
at net.minecraft.class_437.method_25412(class_437.java:434)

-- Affected screen --
Details:
Screen name: me.shedaniel.rei.gui.RecipeViewingScreen
Stacktrace:
at net.minecraft.class_437.method_25412(class_437.java:434)
at net.minecraft.class_309.method_1466(class_309.java:348)
at net.minecraft.class_309.method_22678(class_309.java:438)
at net.minecraft.class_309$$Lambda$5004/446422468.run(Unknown Source)
at net.minecraft.class_1255.execute(class_1255.java:94)
at net.minecraft.class_309.method_22676(class_309.java:438)
at net.minecraft.class_309$$Lambda$3651/1035383700.invoke(Unknown Source)
at org.lwjgl.glfw.GLFWKeyCallbackI.callback(GLFWKeyCallbackI.java:37)
at org.lwjgl.system.JNI.invokeV(Native Method)
at org.lwjgl.glfw.GLFW.glfwPollEvents(GLFW.java:3101)
at com.mojang.blaze3d.systems.RenderSystem.flipFrame(RenderSystem.java:109)
at net.minecraft.class_1041.method_15998(class_1041.java:308)
at net.minecraft.class_310.method_1523(class_310.java:1041)
at net.minecraft.class_310.method_1514(class_310.java:654)
at net.minecraft.client.main.Main.main(Main.java:215)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at net.fabricmc.loader.game.MinecraftGameProvider.launch(MinecraftGameProvider.java:192)
at net.fabricmc.loader.launch.knot.Knot.init(Knot.java:140)
at net.fabricmc.loader.launch.knot.KnotClient.main(KnotClient.java:26)

-- Affected level --
Details:
All players: 1 total; [class_746['Br00t4L17y'/338013, l='ClientLevel', x=-586.72, y=65.00, z=-2025.48]]
Chunk stats: SodiumChunkCache: 625
Level dimension: minecraft:overworld
Level spawn location: World: (-256,68,-80), Chunk: (at 0,4,0 in -16,-5; contains blocks -256,0,-80 to -241,255,-65), Region: (-1,-1; contains chunks -32,-32 to -1,-1, blocks -512,0,-512 to -1,255,-1)
Level time: 31775566 game time, 34721614 day time
Server brand: fabric
Server type: Non-integrated multiplayer server

-- System Details --
Details:
Minecraft Version: 1.16.1
Minecraft Version ID: 1.16.1
Operating System: Windows 10 (amd64) version 10.0
Java Version: 1.8.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 6852311056 bytes (6534 MB) / 8589934592 bytes (8192 MB) up to 8589934592 bytes (8192 MB)
CPUs: 8
JVM Flags: 9 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xss1M -Xmx8G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M
Fabric Mods:
adorn: Adorn 1.9.1+1.16.1
aopalliance_aopalliance: aopalliance 1.0
artofalchemy: Art of Alchemy 1.0.0-rc2+1.16.1
autoconfig1u: Auto Config v1 Updated 3.2.0-unstable
beenfo: Beenfo 1.16-fabric0.13.1-1.1
blue_endless_jankson: jankson +
bunch-o-trinkets: Bunch O' Trinkets 1.0.1
cardinal-components-base: Cardinal Components API (base) 2.4.0
cardinal-components-entity: Cardinal Components API (entities) 2.4.0-nightly.1.16-rc1.build.2
cardinal-components-item: Cardinal Components API (items) 2.4.0
cavebiomes: Cave Biomes 0.2.3
cloth-basic-math: Cloth Basic Math 0.5.1
cloth-client-events-v0: Cloth Client Events v0 1.0.4
cloth-config2: Cloth Config v4 4.5.6
com_electronwill_night-config_core: core 3.6.0
com_electronwill_night-config_toml: toml 3.6.0
com_fasterxml_jackson_core_jackson-annotations: jackson-annotations 2.9.0
com_fasterxml_jackson_core_jackson-core: jackson-core 2.9.0
com_fasterxml_jackson_core_jackson-databind: jackson-databind 2.9.0
com_fasterxml_jackson_dataformat_jackson-dataformat-yaml: jackson-dataformat-yaml 2.9.0
com_fasterxml_jackson_module_jackson-module-kotlin: jackson-module-kotlin 2.9.0
com_github_therandomlabs_trlutils-config: TRLUtils-Config master-SNAPSHOT
com_github_therandomlabs_trlutils-fabric: TRLUtils-Fabric 1.16-SNAPSHOT
com_google_inject_guice: guice 4.2.3
cotton: Cotton 1.0.5
cotton-cauldron: Cotton Cauldron 1.0.4
cotton-commons: Cotton Commons 1.0.4
cotton-config: Cotton Config 1.0.0-rc.7
cotton-datapack: Cotton Datapack 1.0.5
cotton-logging: Cotton Logging 1.0.0-rc.4
cotton-player-events: Cotton Player Events 1.0.2
essentials-base: Essentials 0.2.3+1.16.1
extraalchemy: Extra Alchemy 1.0.3
fabric: Fabric API 0.14.1+build.372-1.16
fabric-api-base: Fabric API Base 0.1.3+12a8474c7c
fabric-biomes-v1: Fabric Biomes (v1) 0.2.7+059ea86602
fabric-blockrenderlayer-v1: Fabric BlockRenderLayer Registration (v1) 1.1.4+c6a8ea8902
fabric-command-api-v1: Fabric Command API (v1) 1.0.8+5ce5339802
fabric-commands-v0: Fabric Commands (v0) 0.2.0+52d3083602
fabric-containers-v0: Fabric Containers (v0) 0.1.8+045df74f02
fabric-content-registries-v0: Fabric Content Registries (v0) 0.1.9+059ea86602
fabric-crash-report-info-v1: Fabric Crash Report Info (v1) 0.1.2+b7f9825d02
fabric-diagonal-panes: Fabric Diagonal Panes 0.3.0
fabric-dimensions-v1: fabric-dimensions-v1 1.0.0+a71b305302
fabric-events-interaction-v0: Fabric Events Interaction (v0) 0.3.3+7066030f02
fabric-events-lifecycle-v0: Fabric Events Lifecycle (v0) 0.2.0+16acbe5b02
fabric-item-api-v1: Fabric Item API (v1) 1.0.0+16acbe5b02
fabric-item-groups-v0: Fabric Item Groups (v0) 0.2.0+438f963602
fabric-key-binding-api-v1: Fabric Key Binding API (v1) 1.0.0+e16a977402
fabric-keybindings-v0: Fabric Key Bindings (v0) 0.2.0+3fa9f7c502
fabric-language-kotlin: Fabric Language Kotlin 1.3.72+build.1
fabric-lifecycle-events-v1: Fabric Lifecycle Events (v1) 1.0.0+b0993bc102
fabric-loot-tables-v1: Fabric Loot Tables (v1) 0.1.10+059ea86602
fabric-mining-levels-v0: Fabric Mining Levels (v0) 0.1.2+b764ce9902
fabric-models-v0: Fabric Models (v0) 0.1.0+dfdb52d602
fabric-networking-blockentity-v0: Fabric Networking Block Entity (v0) 0.2.5+b50ffc7b02
fabric-networking-v0: Fabric Networking (v0) 0.1.10+e00ecb5f02
fabric-object-builder-api-v1: Fabric Object Builder API (v1) 1.5.5+e00ecb5f02
fabric-object-builders-v0: Fabric Object Builders (v0) 0.6.0+da175ad602
fabric-particles-v1: fabric-particles-v1 0.2.1+0a6f2a7002
fabric-registry-sync-v0: Fabric Registry Sync (v0) 0.3.8+7dba2d6c02
fabric-renderer-api-v1: Fabric Renderer API (v1) 0.2.13+eae12eb802
fabric-renderer-indigo: Fabric Renderer - Indigo 0.3.2+4d66bed502
fabric-renderer-registries-v1: Fabric Renderer Registries (v1) 2.0.1+5a0f9a6002
fabric-rendering-data-attachment-v1: Fabric Rendering Data Attachment (v1) 0.1.3+b7f9825d02
fabric-rendering-fluids-v1: Fabric Rendering Fluids (v1) 0.1.8+b7084faa02
fabric-rendering-v0: Fabric Rendering (v0) 1.1.0+5341049002
fabric-rendering-v1: Fabric Rendering (v1) 1.1.2+346247d702
fabric-resource-loader-v0: Fabric Resource Loader (v0) 0.2.6+f41e209802
fabric-screen-handler-api-v1: Fabric Screen Handler API (v1) 1.0.1+f362c86e02
fabric-tag-extensions-v0: Fabric Tag Extensions (v0) 0.2.7+a4c57d8e02
fabric-textures-v0: Fabric Textures (v0) 1.0.4+eae12eb802
fabric-tool-attribute-api-v1: Fabric Tool Attribute API (v1) 1.1.4+5794386e02
fabricloader: Fabric Loader 0.9.0+build.204
glassdoor: Glass Doors 1.4.4-1.16
glassential: Glassential 1.16.1-1.1.4
gubbins: Gubbins 1.1.1-1.16.1
inmis: Inmis 1.1.1-1.16.1
inventorysorter: Inventory Sorter 1.7.0-1.16
jankson: Jankson 3.0.0+j1.2.0
javax_inject_javax_inject: javax.inject 1
kyrptconfig: Kytpt Config 1.0.4-1.16
libcd: LibCapableData 2.4.1+1.16-pre2
libgui: LibGui 2.0.1+1.16.1
libstructure: Libstructure 1.3
lithium: Lithium 0.5.0
minecraft: Minecraft 1.16.1
modmenu: Mod Menu 1.12.2+build.17
mysql_mysql-connector-java: mysql-connector-java 5.1.46
org_javassist_javassist: javassist 3.26.0-GA
org_jetbrains_annotations: annotations 17.0.0
org_jetbrains_exposed_exposed-core: exposed-core 0.23.1
org_jetbrains_exposed_exposed-java-time: exposed-java-time 0.23.1
org_jetbrains_exposed_exposed-jdbc: exposed-jdbc 0.23.1
org_jetbrains_kotlin_kotlin-reflect: kotlin-reflect 1.3.72
org_jetbrains_kotlin_kotlin-stdlib: kotlin-stdlib 1.3.72
org_jetbrains_kotlin_kotlin-stdlib-jdk7: kotlin-stdlib-jdk7 1.3.72
org_jetbrains_kotlin_kotlin-stdlib-jdk8: kotlin-stdlib-jdk8 1.3.72
org_jetbrains_kotlinx_kotlinx-coroutines-core: kotlinx-coroutines-core 1.3.7
org_jetbrains_kotlinx_kotlinx-coroutines-jdk8: kotlinx-coroutines-jdk8 1.3.7
org_postgresql_postgresql: postgresql 42.2.2
org_reflections_reflections: reflections 0.9.12
org_slf4j_slf4j-api: slf4j-api 1.8.0-beta1
org_xerial_sqlite-jdbc: sqlite-jdbc 3.28.0
org_yaml_snakeyaml: snakeyaml 1.26
parchment: Parchment 1.0.2+1.15.2
phosphor: Phosphor 0.6.0+build.7
playerabilitylib: Pal 1.2.0
reach-entity-attributes: Reach Entity Attribute 1.0.1
reborncore: Reborn Core 4.3.1+build.35
roughlyenoughitems: Roughly Enough Items 4.7.0
shapes: Shapes 2.0.0+build.10
sodium: Sodium 0.1.0
soulbound: Soulbound 1.0.1
spinnery: Spinnery 3.0.48
step-height-entity-attribute: Step Height Entity Attribute 1.0.0
team_reborn_energy: Energy 0.1.0
techreborn: Tech Reborn 3.4.2+build.48
terraform: Terraform 2.1.6+build.30
terrestria: Terrestria 2.0.2+build.29
trinkets: Trinkets 2.6.2
universalcomponents: Universal Components 0.7.2+1.16-pre2
vanilladeathchest: VanillaDeathChest 1.16.1-1.11.0.3-fabric
voxelmap: VoxelMap 1.10.4
waila: Hwyla 1.9.22
winged: Winged Mod 1.16-1.2
Launched Version: fabric-loader-0.9.0+build.204-1.16.1
Backend library: LWJGL version 3.2.2 build 10
Backend API: Radeon RX 570 Series GL version 4.6.13559 Compatibility Profile Context 26.20.12028.2, ATI Technologies Inc.
GL Caps: Using framebuffer using OpenGL 3.0
Using VBOs: Yes
Is Modded: Definitely; Client brand changed to 'fabric'
Type: Client (map_client.txt)
Resource Packs: vanilla, virtual/fabric-diagonal-panes:models
Current Language: English (US)
CPU: 8x Intel(R) Core(TM) i7-6700K CPU @ 4.00GHz`

You have an outdated version of Inmis. Update to 2.0.0 and let me know if the issue persists. Your REI version is also slightly outdated (4.7 vs 4.10), so you might also want to try updating that. I'm able to view REI recipes from a backpack GUI without a crash in my development environment.