Cannot type capital letters in Insert mode

I'm sure this is a bad configuration or some interaction with another plugin, but I can't figure it out, and GitHub discussions is not enabled on this repo, so submitting a bug report.

Describe the bug
Can't use shift in insert mode to enter uppercase letters.

To Reproduce
Open any file with, switch to insert mode, try to enter uppercase letters. Some of the keys work, but for example shift-d or shift-i don't work.

Expected behavior
Shift + letters should work in insert mode, insert an uppercase letter.

Environment (please complete the following information):

• Extension (VsCodeVim) version: latest
• VSCode version: latest
• OS: linux

Additional context
Full config:

{
    "telemetry.enableCrashReporter": false,
    "telemetry.enableTelemetry": false,
    "editor.fontFamily": "'Jetbrains Mono Medium'",
    "workbench.colorTheme": "Gray Matter Dark",
    "files.watcherExclude": {
        "**/target/**": true
    },
    "editor.lineNumbers": "off",
    "window.zoomLevel": 1,
    "editor.cursorBlinking": "solid",
    "editor.cursorStyle": "block",
    "breadcrumbs.enabled": true,
    "vim.leader": ",",
    "vim.useCtrlKeys": true,
    "vim.handleKeys": {
        "<C-f>": false,
        "<C-]>": false,
        "<C-[>": false,
        "<C-b>": false,
        "<C-k>": false,
    },
    "vim.insertModeKeyBindings": [
        {
            "before": [
                "j",
                "k"
            ],
            "after": [
                "<Esc>"
            ]
        },
        {
            "before": [
                "k",
                "j"
            ],
            "after": [
                "<Esc>"
            ]
        }
    ],
    "vim.normalModeKeyBindings": [
        {
            "before": [
                "H"
            ],
            "after": [
                "^"
            ]
        },
        {
            "before": [
                "L"
            ],
            "after": [
                "$"
            ]
        },
        {
            "before": [
                "Space"
            ],
            "after": [
                "O",
                "<Esc>"
            ]
        },
        {
            "before": [
                "Enter"
            ],
            "after": [
                "o",
                "<Esc>"
            ]
        }
    ],
    "vim.visualModeKeyBindings": [
        {
            "before": [
                "H"
            ],
            "after": [
                "^"
            ]
        },
        {
            "before": [
                "L"
            ],
            "after": [
                "$"
            ]
        },
    ],
    "editor.renderLineHighlight": "none",
    "editor.renderIndentGuides": false,
    "files.autoSave": "afterDelay",
    "gitlens.blame.ignoreWhitespace": true,
    "editor.minimap.enabled": false,
    "scm.diffDecorations": "gutter",
    "C_Cpp.updateChannel": "Insiders",
    "[rust]": {
        "editor.defaultFormatter": "matklad.rust-analyzer"
    },
    "gitlens.advanced.repositorySearchDepth": 2,
    "editor.wordWrapColumn": 100,
    "vim.textwidth": 100,
    "terminal.integrated.fontSize": 13,
    "editor.semanticHighlighting.enabled": true,
    "rust-analyzer.cargo.allFeatures": false,
    "rust-analyzer.checkOnSave.allFeatures": false,
    "editor.fontLigatures": true,
    "debug.console.fontSize": 13,
    "extensions.ignoreRecommendations": true,
    "editor.fontSize": 13,
    "search.useGlobalIgnoreFiles": true,
    "editor.renderWhitespace": "none",
    "editor.find.cursorMoveOnType": false,
    "editor.tokenColorCustomizations": {
        "[Solarized Light]": {
            "variables": "#002b36",
            "functions": "#002b36",
        },
        "[Gray Matter Dark]": {
            "comments": "#969caf"
        },
        "[Gray Matter Light]": {
            "comments": "#969caf"
        }
    },
    "editor.semanticTokenColorCustomizations": {
        "[Solarized Light]": {
            "enabled": true,
        },
        "[Gray Matter Dark]": {
            "enabled": false,
        }
    },
    "workbench.colorCustomizations": {
        "[Gray Matter Dark]": {
            "editor.background": "#282a36",
            "sideBar.background": "#282a36",
        }
    },
    "workbench.iconTheme": "vs-seti",
}

No source file or test is named. Start by reproducing the issue in VSCodeVim Insert mode on Linux with the reported configuration, then trace how shifted keys are handled; done means Shift plus letters, including D and I, inserts uppercase characters.